WO2022167412A1

WO2022167412A1 - Air-purifying respirator

Info

Publication number: WO2022167412A1
Application number: PCT/EP2022/052340
Authority: WO
Inventors: Louis-Philippe Mascart; Marie-Paule KIRSCHT
Original assignee: Bioneering
Priority date: 2021-02-03
Filing date: 2022-02-01
Publication date: 2022-08-11
Also published as: EP4288160A1; BE1029078B1; BE1029078A1

Abstract

Disclosed is an air-purifying respirator that comprises an annular base (1), which has a central opening and means for receiving a hood (5) forming a transparent hollow body in which the head of the user can be accommodated, and an aeration system (2), which is mounted on the annular base and forms with the latter a supply circuit for supplying filtered fresh air to the hood. Said aeration system (2) comprises a filtering inlet element, an exhaust circuit for discharging filtered used air from the hood and a filtering outlet element. The circuit for supplying filtered fresh air is provided with a compressor for drawing surrounding air through the filtering inlet element.

Description

AIR PURIFYING RESPIRATOR

The present invention relates to an air-purifying respirator.

Devices of this kind are known which are intended to protect nursing staff from infection by infectious agents, such as viruses, microbes, etc., which may be in the ambient atmosphere while they are working on patients. . These in particular can produce and release these infectious agents into the environment, for example by exhaling or projecting jets or liquid or solid particles, and transmit them to healthcare personnel, if they are not protected. We therefore provide, to protect him, insulating suits or aprons which cover the body. The head is covered with a flexible or rigid hood, completely transparent or provided with a transparent visor.

A ventilation system is also provided to allow the user to breathe. Prefiltered air is introduced into the hood by means of this system, which is worn outside the hood and transfers the filtered air inside it. The hood can in particular be equipped with the ventilation system directly in front of the face, like a gas mask, or at its top, the system being worn directly on the skull. These systems are impractical because they interfere with the user's vision or the freedom of movement of their head inside the hood. In other cases, the ventilation system is attached to the user's belt or back, for example, and connected to the hood by a long flexible conduit.

The object of the present invention is to develop an air-purifying respirator which makes it possible to protect not only the nursing staff of the patient, but also the patient from the nursing staff. In fact, in the event of epidemics, healthcare personnel may also be carriers of the infectious agent and spread it in the environment through the air they exhale. Advantageously, this respirator will allow maximum freedom of movement at the head of the nursing staff during their intervention. To solve these problems, there is provided, according to the invention, an air-purifying respirator comprising: i) an annular base, which has a central opening allowing free passage of a user's head and means for receiving a hood, this annular base having a front part and a back part, opposite the front part, ii) a hood adapted to be supported by said annular base, said hood forming an at least partially transparent hollow body having an internal volume in which said user's head can be housed in a freely movable manner and comprising at least one rigid part which can be detachably connected with the annular base, and iii) a ventilation system mounted on said dorsal part of the base annular and forming with this base a circuit for supplying fresh filtered air to the hood and a circuit for evacuating filtered used air from the hood, said supply circuit connection connecting a fresh air inlet arranged on said ventilation system to a filtered fresh air supply provided on said base and comprising an inlet filtering element arranged at said fresh air inlet, said evacuation circuit connecting a used air exhaust provided on said base at a filtered used air outlet disposed on said ventilation system and comprising an outlet filter element at said used air outlet, said filtered fresh air supply and said exhaust of used air being in fluid communication with said interior volume of the hood, said filtered fresh air supply circuit being provided with a compressor arranged to extract surrounding air through the inlet filter element.

In this air-purifying respirator, the user's head is perfectly free to move, because there is no contact, whether with the hood or with the base, and the user's head is not wearing anything. According to the invention, use has been made of the term hood usually used in the surgical field to designate the protective element of the head. In the present invention, this hood is at least partially rigid so as not to be in contact with the user's face. Preferably, the wall of the hood can be totally rigid and form a kind of helmet. By rigid wall is meant that it is self-supporting around the head of the user. Its thickness can however be very small, of the order of 0.3 or even 0.1 mm for example, to allow the transmission of sounds. Advantageously, the hollow body of the hood has, at the periphery, a transparent wall over at least 65% of the periphery, to provide the user with maximum vision and simultaneously a top and/or rear part that is only translucent or even opaque. Preferably, the hollow body of the hood is completely transparent. The hood may have a cylindrical, conical, frustoconical, spherical or other shape provided that it guarantees the freedom of movement of the user's head, without contact with him, and that at its base it is adapted to the shape of the ring base. This may indeed have the shape of a circular, elliptical, polygonal or other ring.

Furthermore, the annular base and the ventilation system mounted on it together form two circuits, one for the circulation of fresh filtered air towards the inside of the hood and the other for the circulation of filtered used air. to the external environment. Used air means air that has already been used at least partially for the user to breathe. The filtrations are carried out by inlet and outlet filtering elements known per se for the filtration of infectious agents, in particular microscopic ones.

More particularly, the filtrations are carried out by a first inlet filter element and a second outlet filter element. The presence of input and output filtering elements, separate from each other, allows bidirectional protection in a particularly advantageous manner.

Indeed, the air-purifying respirator according to the present invention makes it possible to preserve the internal space of the hood from the air coming from the external environment but also to preserve the external environment from the air coming from the internal space of the hood.

Advantageously, the inlet and outlet filter elements are filters. Particularly advantageously, the inlet and outlet filters are HEPA filters, for example of the H13 type, allowing filtration at 0.3 to 0.1 m. HEPA filters, for example of type H 13, make it possible to filter approximately 99.95% of infectious agents. Compared to an FFP2 type mask or filter, does not filter infectious agents than 95%. In addition, the inlet and outlet filters of the respirator according to the present invention have a surface area approximately 20 times greater than that of an FFP2 type filter and compared to the filters used according to the prior art.

The use of H13 type HEPA inlet and outlet filters, more preferably the use of large surface HEPA inlet and outlet filters, leads to a very low pressure drop. The energy required by the compressor to obtain a renewal air flow inside the hood is therefore lower compared to conventional filters.

By “pressure drop” is meant the resistance of the filter to the passage of air, or more exactly, the reduction in the flow of air due to the resistance of the filter to the passage of air. The higher the “pressure drop”, the greater the reduction in airflow.

In addition, with the compressor operating at a low percentage of its maximum flow, it is possible at any time to increase the airflow to give a "comfort cooling" effect in addition to the base flow, and regulated according to the intensity of the user's physical effort. This also reduces the sound level of the compressor, offering more comfort to the user.

In a particularly advantageous manner, the respirator according to the present invention makes it possible to prevent contamination of the air inside the hood coming from outside and/or to prevent the release of infectious agents from inside the hood. towards the surrounding environment. Indeed, the presence of inlet and outlet filtering elements, preferably type H 13 HEPA filters, allows even in the event of a breakdown of the compressor and/or the purifying respirator, that the user can continue to breathe through filters, unassisted for at least 15 minutes, without experiencing breathing difficulties or tightness. Thanks to the presence of inlet and outlet filtering elements, with or without compressor assistance, the user's blood remains perfectly oxygenated at all times.

Finally, the inlet and outlet filters also have the advantage of having a lifespan of more than 5 years, given the cleanliness of the air in surgical operating rooms or clean rooms. Advantageously, at least one activated carbon pre-filter is positioned before the air inlet filter, this making it possible to carry out a pre-filtration of the largest particles, this further increasing the service life of the filters.

Advantageously, the filtered used air evacuation circuit can also be provided with an additional compressor which is arranged to extract used air from the hood through the outlet filtering element. As compressor or fan, use can be made of elements known per se.

Advantageously, the circulation circuit of filtered fresh air towards the inside of the hood, makes it possible, by means of the compressor, to maintain the air inside the hood at a slight overpressure. This allows in the event of a leak from the hood, that the movement of air is constantly carried out from the inside of the purifying respirator to the outside, thus protecting the user from outside air and outside contamination.

A source of electrical energy is of course to be provided for the implementation of the compressor(s) or other electrically operated elements, such as indicator lights for example. Preferably, the filtered used air evacuation circuit of the aeration system is equipped with a flow measurement element arranged to measure the flow at the used air outlet and adjust the compressor so that the flow at the used air outlet is at all times positive with respect to the pressure at the fresh air inlet. Indeed, it is necessary to avoid a reverse flow of air in the outlet filter element and thus a release of the contaminants it contains inside the hood.

Advantageously, the flow measurement element is placed on the evacuation circuit connecting a used air exhaust. This positioning makes it possible to effectively measure the sum of the flow rate of the compressor and the breathing of the user. Given that the frequency and amplitude of the user's breathing are directly linked to his physical effort, this information makes it possible to adapt the air flow rate of the inlet and/or outlet compressor(s). This advantageously makes it possible to provide a sufficient air flow to have sufficient oxygenation of the user in all circumstances while limiting the sound volume of the compressor. Advantageously, the user can modify the parameters of the respirator according to the present invention, for example to increase or decrease the incoming air flow, and this manually using the control means present on the air purifier and / or remotely, for example using a central control unit connected to the air-purifying respirator according to the invention.

For example, when a surgeon is equipped with the air-purifying respirator according to the present invention, it turns out that the latter, for reasons of sterility and contamination, cannot touch anything in the operating room other than his sterile tools and the patient. It is particularly advantageous for the respirator according to the present invention to be connected to a central remote control unit, for example by means of a Wifi, Bluetooth or other connection, and for a third party to be able to adjust the flow rate parameters of remote air.

This advantageously makes it possible to provide a sufficient airflow for oxygenation, comfort and also to provide a cooling effect to the user in addition to the basic airflow regulated according to the intensity of the physical effort. Thus, the respirator according to the invention offers great comfort to the user who may regularly find himself under a heat source such as a projector with halogen lamps, or under the sun outdoors.

Advantageously, the air-purifying respirator according to the present invention comprises a temperature sensor, preferably arranged inside the hood. Such a temperature sensor being arranged to actuate an additional, more intense flow of air, having the effect of providing a comfort cooling effect when a predetermined temperature threshold is reached inside the purifying respirator according to the invention. , especially inside the hood.

In addition, a temperature sensor, positioned inside the hood, is arranged to detect the presence of a user by measuring the latter's body heat, and in such a case to automatically start the compressor(s). ) of the air-purifying respirator according to the present invention.

According to one embodiment of the invention, the annular base comprises an upper face bearing the means for receiving the hood and a lower face, the upper face comprising an outer peripheral surface, an annular shoulder projecting upwards, arranged to center said hood when the latter is placed on the base, and an inner peripheral surface, the outer peripheral surface being arranged to form a support for the hood. This arrangement allows easy and quick centered removal of the hood on the annular base, in particular on the means for receiving it.

Advantageously, the hood has a front part to be placed facing the user and the inner peripheral surface of said annular base comprises, as aforesaid fresh air supply in the hood, one or more orifices in the front part of the base to form a curtain of fresh air rising along said front part of the hood, inside the latter. This arrangement makes it possible to avoid fogging up the front part of the hood, that is to say the part located in front of the user's face.

According to a particular form of the invention, the air-purifying respirator comprises one or more control means chosen from among means for controlling the charge of the energy source, means for controlling the quality of the filtering elements, means for control of leaks from the hood or alternatively means for detecting the mutual engagement between the hood and the annular base. These means can in particular be carried on the annular base or the ventilation system. In the front part of the annular base, one or more light and/or sound indicators can be connected to said control means and be arranged to emit a light and/or sound signal in response to a signal from the control means.

Advantageously, the power supply and/or charge level of the electrical energy source can be signaled by at least one light and/or sound indicator. This alerts the user to the power/charge status of the electrical power source. Thus, advantageously, the user can quickly realize that the source of electrical energy must be replaced, or that it is defective which could hinder the operation of the air-purifying respirator. Advantageously, the level of air leakage from the air-purifying respirator can be signaled by at least one light and/or sound indicator. This allows the user to quickly recognize that there is a problem with the air-purifying respirator, and that contaminated air may be leaking from the air-purifying respirator, or in the case of a large leak that outside air can enter the respirator according to the invention.

Advantageously, the source of electrical energy may in particular be a portable element such as a cell or a battery, to be recharged or replaced after a predetermined time, this cell or battery being able to be supported by the ventilation system, the annular base or any other suitable medium. Advantageously, the source of electrical energy can be removable, for example a removable battery or cell. This advantageously makes it possible to replace it if it is faulty, and to facilitate sterilization between two refills and subsequent recycling.

In addition, it is particularly advantageous for the source of electrical energy, the compressor, the flow measurement element, a control microprocessor, to be positioned within a common casing. This advantageously makes it possible to recover the box directly and easily, and to carry out the sterilization and reuse of the equipment.

According to one embodiment, the purifying respirator comprises a source of emergency electrical energy, for example a battery or an emergency cell. This allows the purifying respirator according to the invention to be able to continue to operate if the source of electrical energy (main) is exhausted or is defective. The user can thus advantageously replace the main power source without interrupting the air-purifying respirator. This backup electrical energy source is preferably removable, for example a backup battery or a removable backup battery.

In addition, the one or more indicators, for example luminous and/or two-color LED are located in the front part of the annular base.

In a particularly advantageous embodiment of the respirator according to the present invention, the hood is made of at least partially reflective material in order to reflect the one or more luminous indicators on the inside of the hood. This makes it possible to easily view the one or more light signals without the user having to constantly look down, thus avoiding having to visually focus too closely on the indicator lights. The comfort of the user is thus increased, by reducing the number of movements and eye fatigue. Furthermore, the safety of the respirator according to the invention is increased, by preventing the user from forgetting to look at the light signals. Indeed, it may be possible to miss crucial information on sterility, the condition of the filtering elements, or the level of charge of the electrical energy source when the light signals are not directly visible or require additional action at the user.

Advantageously, the one or more sound indicator is a buzzer or loudspeakers. The buzzer or sound indicator presents a different sound sequence depending on the subject of the alarm. This allows the user to know almost immediately the parameter concerned by this alert (discharged or underpowered source of electrical energy, air leak, etc.). Advantageously, the purifying respirator according to the invention may also comprise one or more means for controlling the circulation of air in the aforementioned supply and evacuation circuits, which are provided on the annular base, in the frontal part thereof, and can be operated manually, for example in the form of control buttons. This allows the user to adjust the air pressure in the hood in the way that suits him, and this in a very easy way. Control means may also be provided to react to signals from said detection means. The compressor(s) start for example automatically, when the detection means observe the removal of the hood on the annular base.

In an advantageous embodiment, the air-purifying respirator according to the present invention is connected, for example via Bluetooth or Wifi, to a control and traceability system. The control and traceability system comprising an equipment assembly validation base and/or an equipment disassembly base.

Furthermore, the air-purifying respirator according to the present invention and the control and traceability system are in permanent communication, in real time. The assembly validation base comprises a user identity or identifier reader, means for reading and/or receiving information from the respirator according to the present invention, for example a unique identification the hood, the filtering elements, the annular base, or any other element making up the respirator.

When the user equips himself with the purifying respirator according to the present invention, assembly information, step by step, as well as the timestamp of the steps, will be transmitted to the validation base.

The equipment disassembly base works similarly, when the user is going to un-equip the respirator according to the present information, disassembly information, step by step, as well as the step timestamp, failure history, the history of the alarms, the time of the stoppage of the work assignment, previously recorded in the electronic system of the hood, will be transmitted to the disassembly base.

The assembly base and/or the disassembly base comprise a Bluetooth or Wifi communication system to be connected to a computer, for example a laptop computer, which makes it possible to centralize the complete traceability of the respirator according to the present invention, as well as incidents, users.

Furthermore, the air-purifying respirator according to the present invention comprises an electronic automatic control device, arranged to activate the circulation of air via the compressor when the control condition provided by the assembly base is met, and/or arranged not to activate the circulation of air via the compressor and/or to emit an alert signal when the control condition provided by the assembly base is not fulfilled.

For example, the activation of the air circulation via the compressor can take place when the correct positioning of the hood on the ring base and/or of the hood and ring base assembly on the chest plate is detected.

Alternatively, in one embodiment of the air-purifying respirator according to the present invention, the hood and the annular base may form a single piece. In the same way, the stopping of the circulation of air via the compressor can take place when the positioning of the hood on the annular base is broken or disengaged.

Advantageously, the validation base is equipped with an information reader making it possible to record and provide multiple information such as the identity of the user, the date and time of validation of the assembly, the load of the energy source, the power supply level of the energy source, the quality of the filtering elements, the presence of leaks at the level of the previously identified hood or information on the mutual engagement between the hood and the base annular.

Advantageously, the purifying respirator according to the invention can after use be checked on the basis of disassembly. The disassembly base is equipped with an information reader to record and provide multiple information such as user identity, date and time of disassembly, power source load , the power supply level of the energy source, the quality of the filtering elements, the presence of leaks at the level of the hood or information on the mutual engagement between the hood and the annular base. The disassembly database also makes it possible to check the history of breakdowns and alarms.

According to a particularly advantageous embodiment, the assembly validation base and the disassembly base are one and the same unit.

Advantageously, the purifying respirator communicates with the assembly and/or disassembly base by wireless communication, for example Bluetooth, Wifi, Infrared, NFC or any other appropriate means.

Advantageously, a management computer is connected to the assembly validation base and/or to the disassembly base and/or to the respirator according to the present invention. The computer can remotely access and/or manage all the parameters collected by the aforementioned base(s). Preferably, the data can be viewed/managed in real time. This allows in conditions where users cannot touch their equipment with the hands, for example in a surgical operating room or in clean rooms, to a manager to adjust the parameters from a computer.

According to a particularly advantageous embodiment of the invention, the purifying respirator further comprises a support member to be arranged on the shoulders and/or the thorax of the user and intended to be detachably connected to said annular base on which said hood can be mounted. The respirator is thus supported by the upper body, but without interfering with the movements of the user's neck and head.

Advantageously, the support member comprises a part in the form of a breastplate to be fixed on the shoulders and/or the thorax of the user and a neck part having a central opening allowing free passage of the user's head, the neck part being supported by the part in the form of a plastron and being provided with a collar projecting outwards presenting an upper surface, this upper surface and the said lower face of the annular base having fastening means allowing engagement mutual centered and detachable. The collar part thus has the shape of a neck brace around the neck of the user, without contact with the latter. This collar part can be solid or perforated. Preferably, in order to ensure sealing, the neck part is solid.

The flexible material annular protection part creates a pneumatic seal between the user's chest and the air-purifying respirator.

The annular protection piece thus offers an effective barrier against external and/or internal contamination of the purifying respirator. In addition, its shape makes it easy to clean. The annular protection piece is also capable of withstanding sterilization and/or decontamination processes. It has the advantage of being particularly pleasant in contact with the skin and allows the use of standard overalls with a collar fitted closely to the neck. In one embodiment, the support member comprises straps in order to fix the part in the form of a breastplate to the body of the user.

Indeed, the annular protection piece is arranged to be positioned between the annular base and the user's outfit, so that in practice, the user first equips (in a simplified manner) his outfit, equips the annular protection piece, equips his work overalls over it, the annular protection piece thus finding itself trapped between the user's outfit and the work overalls, then the user finally equips the respirator according to the present invention above above.

In one embodiment of the present invention, the first annular protection piece is directly linked to the annular base.

This allows the user, as explained above, to equip the annular protection piece, the annular base, the hood and the ventilation system in order to have the air-purifying respirator according to the present invention, sealed to the external environment, thus avoiding incoming and outgoing contamination thanks to the pneumatically sealed material of the annular protection part and its positioning under the annular base.

Advantageously, the air-purifying respirator according to the present invention comprises a second annular protection part, for example made of a flexible material such as flexible plastic, having a large overlap zone.

Indeed, the second annular protection part having a large overlap zone is arranged to be coated with low-strength glue in order to cover the two faces of the overlap of the second annular protection part, and to cover the first annular protection part. The second piece of annular protection being for single use and having to be easily removed for disposal.

Indeed, according to the simplified mode of equipment described above, it appeared that users, surgeons, dentists, doctors or any other person who can use the respirator according to the present invention can work in a highly contaminated or contaminating environment.

In such a case, the user can equip the second piece of annular protection, above the work overalls to cover the first piece of annular protection and the overalls, and then put on a disposable apron over it to finally equip the respirator according to the present invention. This makes it possible, in such an environment, to easily remove and dispose of both the disposable apron and the second piece of disposable annular protection. Advantageously, in another embodiment, the support member comprising a part in the form of a breastplate, also comprises a rod descending to the level of the lower kidneys of a user, this allowing better stabilization of the respirator according to the present invention by compared to the breastplate comprising only straps. The breastplate and the upper being held in place by the user's protective clothing (of the apron or overalls type). This keeps the breastplate in place and without play on the bust.

Advantageously, in another embodiment, the support member is arranged on the shoulders and/or the hips of the user. More particularly, the support member comprises a backpack. Preferably, this backpack includes 2 shoulder straps.

Advantageously, the backpack of the support member comprises at least one hip strap, arranged to rest on the hips of the user and thus distribute the weight of the respirator according to the present invention on the lower limbs of the user and not on the upper limbs.

Indeed, this is particularly advantageous in the context of a user equipped with the respirator according to the present invention to carry out long operations, for example a surgeon. Such an embodiment of the support member of the respirator according to the present invention makes it possible to avoid significant back pain, and in the long term, back complaints due to the constant carrying of a load.

The height of the support member comprising a backpack is advantageously adjustable by means of a sliding and lockable plate. This makes it possible to best adjust the height according to the user and thus perfectly position the hood as well as the hip straps, for all sizes and morphologies of users.

Conveniently, the means for fixing the support member comprise centering pins projecting upwards from the upper surface of the first collar and locking holes intended to receive these pins, in the face bottom of the ring base. According to a particular form of the invention, the purifying respirator comprises, in the position of engagement of said upper surface of said first collar and of said lower face of said annular base by said fixing means, a washer of flexible material which is inserted between said upper surface and said lower face, is traversed by the fixing means and has an internal peripheral edge projecting inwardly from the neck portion of the support member. Advantageously, the flexible material washer is provided with a drawstring allowing the inner peripheral edge of said washer to be tightened around the user's neck. This allows, after positioning the user's head through the central opening of the neck portion of the support member, the sliding of the flexible material washer around the user's head, fixing of the latter in a manner centered on the support member and sealingly closing the hollow volume of the hood, by tightening the washer around the user's neck.

Advantageously, the washer is made of a pneumatically sealed material/textile capable of reducing the resonances caused by the hood.

Advantageously, the respirator according to the present invention comprises an intercom, preferably behind a material/textile closing the space between the hood and the user's torso, for example the washer. The intercom includes at least one microphone and at least one speaker. The at least one loudspeaker can be located on top of the shoulders near the ears and/or behind the puck. Advantageously, the user can adjust the sound amplification levels. Advantageously, the signals are adjusted by at least one potentiometer or remotely. Advantageously, the potentiometer is capable of being maneuvered through the material/textile.

Advantageously, the hood of the respirator according to the present invention has an upper end surface, from above, made of a pneumatically sealed material/textile capable of reducing resonances.

According to a preferred embodiment of the invention, the purifying respirator comprises, in the engagement position of said upper surface of said first flange and of said lower face of said annular base by said fastening means, an annular protective piece of flexible material which is inserted between said upper surface and said lower face, is traversed by the aforesaid fastening means, and has a covering part which protrudes outwards coating at least partially the support member. Preferably, it covers the entire support member to protect it from any contamination. Advantageously, the annular protection part is provided with a tightening link allowing said cover part to be tightened around the neck part of the support member, below the first collar of the part of collar, while the rest of the covering piece spreads over the user's shoulders like a cape, thus protecting the support member.

Particularly advantageously, the purifying respirator according to the present invention can be sterilized and/or decontaminated.

Indeed, the air-purifying respirator according to the present invention, as well as all the elements which compose it, can be decontaminated and/or sterilized by gamma radiation, dry fog, ethylene oxide, ozone and UVC radiation.

Thus, and in a particularly advantageous manner, each element of the respirator according to the invention and more generally the air-purifying respirator according to the present invention is reusable while minimizing the risks of contamination. In addition, the sterilization and disinfection/decontamination of the respirator according to the present invention makes it possible to considerably reduce the quantity of waste and to reduce the environmental impact.

According to another embodiment of the present invention, the air purifying respirator is disposable. This also makes it possible to limit the risks of contamination in areas/situations where the decontamination infrastructures are not sufficient to ensure secure reuse of the purifying respirator according to the invention. Other details and particularities will become apparent from the description given below, with the aid of the appended drawings which illustrate, without limitation, an air-purifying respirator according to the invention.

Figure 1 shows a perspective view of an air-purifying respirator according to the invention.

Figure 2 shows an enlarged view of a detail from Figure 1.

Figure 3 shows a view of the base of the respirator according to Figure 1, fitted with its ventilation system, but without a hood.

Figure 4 shows a rear view of the base of figure 3 without filter element.

Figure 5 shows a view of the air-purifying respirator according to Figure 1, provided with a tester member.

Figure 6 schematically shows the air circulation in the base equipped with the ventilation system and the hood.

FIG. 7 represents an exploded view of an embodiment of purifying respirator according to the invention, presenting a support member.

Figures 8 to 19 illustrate the successive steps of the dressing procedure.

Figures 20A and 20B illustrate an alternative support member on which the purifying respirator according to the invention is housed.

In the various drawings, the same references designate identical or similar elements.

As shown in Figure 1, the illustrated air-purifying respirator comprises an annular base 1, which has a central opening allowing free passage, without contact, of the user's head. This base has a front part which will face the user's face and a back part to which a ventilation system 2 is attached.

The annular base 1 has an upper face comprising an outer peripheral surface 3, which is arranged to form a support for the hood 5 when the latter is placed on the base 1, an annular shoulder 4 projecting upwards, arranged to center the hood 5, and an internal peripheral surface 6.

The hood 5 illustrated is completely rigid and its wall is completely transparent. It forms a hollow body, here cylindrical, having an interior volume in which the user's head can be housed in a freely mobile manner. In the example illustrated, the hood and the base have detachable mutual engagement means, not shown, known per se, such as those allowing for example a bayonet closure.

As shown in Figures 1 to 6, the aeration system 2 comprises, in the example shown, a filter support 7 and a filter cartridge 8 in which are housed two filter elements 9 and 10, one disposed to the fresh air inlet and the other to the filtered used air outlet. As shown in Figures 4 and 6, the filter support 7 is divided into two housings, the right one being provided to receive a compressor 1 1 arranged to draw in surrounding air through the filter element of inlet 9, this compressor being powered by an electrical energy source 15. This energy source may in particular be a portable element such as a cell or battery, to be recharged or replaced after a predetermined time, this cell or battery being able to be supported by the ventilation system, the ring base or any other appropriate support. The filter cartridge 8 is mounted in an easily detachable manner on the filter support 7 so as to be able to quickly replace the filter elements.

Together, the ventilation system 2 mounted on said dorsal part of the annular base 1 and the base itself form a filtered fresh air supply circuit in the hood 5 and a used air evacuation circuit filtered out of the hood.

As illustrated schematically in Figure 6, the supply circuit communicates a fresh air inlet 12 disposed on the ventilation system 7 with a filtered fresh air supply 13 provided on said annular base 1, at the inside the hood. In the example illustrated in Figures 1 and 2, as a supply of filtered fresh air, there is provided, inside the hollow volume of the hood 5, vents 14 which are arranged on the internal surface 6 of the base parallel to the front part of the hood wall. Through these vents 14, the supplied filtered fresh air can enter the hood by forming a curtain of fresh air rising along this front part, which makes it possible to prevent the hood from fogging up in front of the user's mouth, nose and eyes. The air flow thus formed then rolls up along the cylindrical wall and around the user's head.

The filtered used air evacuation circuit communicates a used air exhaust 16, provided on the annular base and in fluid communication with the interior volume of the hood, with a filtered used air outlet 17. A compressor not shown may be provided in the evacuation circuit to draw used air out of the hood through the outlet filter element 10. This circuit may also be provided with a usual flow measurement element, such as a flowmeter 21, which is arranged to measure the flow rate at the filtered used air outlet and emit an alarm signal when the pressure and more precisely the air flow rate is no longer compliant.

As shown in Figure 2, in the front part of the annular base 1, on the inner peripheral surface 6, several indicator lights 18 and 19 are provided. They are usually connected to control means, not shown, and can emit a light signal in response to a signal from the latter. By their arrangement in front of the face of the user, the latter can be kept informed, for example, of an increase or a decrease in the air flow, the state of charge of the battery or batteries, the the cleanliness of the filters, the presence or absence of air leaks. Means for detecting the mutual engagement between the hood and the annular base can also be envisaged.

In the example illustrated in Figure 1, one can observe, on the front part of the annular base 1, control buttons 20 which for example can be used to adjust the air flow to an appropriate value. Due to their location on the outside of the hood, at the level of the user's neck or chin, these buttons are easily operable manually.

The air-purifying respirator illustrated in Figure 7 or in Figures 20A and 20B, includes a support member 22 to be fitted on the user's shoulders. It is designed to be detachably connected to the annular base 1 before or after the mutual engagement of the hood 5 and the base 1. In the examples illustrated, the support member 22 comprises two parts, a part in the form of a breastplate 23 or a backpack 41, to be fixed to the body of the user by straps 24 or shoulder straps 38, and a collar part 25, in the shape of an openwork neck brace. The neck part 25 has a central opening and a flange 26 projecting outwards. On the upper surface of this collar 26 stand fixing pins 27 allowing centered and detachable mutual engagement with corresponding locking orifices provided on the underside of the annular base 1 .

In the examples illustrated, and as is apparent in particular from FIGS. 8 to 11, the neck part 25 consists of two symmetrical sections 28 and 29 which can slide towards each other or vice versa on the part in form of breastplate 23, or on the part in the form of a backpack 40. In the separated position, these sections allow the user's head to pass between them without contact with it (see FIGS. 8 to 10) while 'after this passage they can be slid into a close position, for example along slides 38, and together form the neck portion 25. At this time the user can put on protective overalls.

Before fixing the annular base 1 on the neck part 25 in the position close to its sections 28 and 29, provision may be made to apply to the collar 26 a washer 30 made of flexible material, for example woven or non-woven fabric. woven or a flexible film, which has a central opening and an inner peripheral edge 31, provided with a drawstring 32 (see Figures 12 to 14). After having slid the user's head through the central opening of the washer 30, it is possible to adjust the latter in a centered manner on the collar 26 by passing the fixing pins 27 through holes corresponding provided on the washer 30. In this position, the inner peripheral edge 31 of the washer protrudes inwardly from the neck portion 25 of the support member 22. The washer 30 can then be tightened around the neck of the user using the cord 32 which is tied. This operation will allow, when the annular base provided with the hood is mounted on the support member, to ensure the sealing of the hollow volume of the hood. It is however possible to envisage ensuring the sealing in question by other means instead of or in addition to the washer 30. It is for example possible to conceive of providing the part in the form of a breastplate with a sealed internal padding 39, for example closed-pore foam. As can be seen from FIGS. 15 to 17, provision may be made, before fixing the annular base 1 on the neck part 25 in the position close to its sections 28 and 29, to apply to the flange 26, or if necessary, on the washer 30, an annular protection piece 33 made of flexible material, for example woven or non-woven fabric or a flexible film, which has a central opening and an outer peripheral edge 34. Between the central opening and the outer peripheral edge 34 is arranged a drawstring 35. After sliding the user's head through the central opening of the protective piece 33, it is possible to adjust it from manner centered on the collar 26 by passing the fixing pins 27 through corresponding orifices provided on the protective part 33. In this position, the outer peripheral edge 34 of the protective part 33 extends well outwards from the flange 26 of the neck part 25 of the support member 22 and spreads like a cape above the latter. It is then possible to tighten the drawstring 35 around the neck part 25. After fixing the annular base 1 on the support member, the protective part is thus inserted between the upper surface of the collar 26 and the face bottom of the base 1, is crossed by the fixing pins 27, and has a covering part 36 which protrudes outwards in the manner of a cape which completely covers the support member, part in the form of breastplate and part in the form of a collar. This arrangement protects the support member from any contamination and it therefore does not need to be cleaned after use of the respirator. At this stage, the user can put on a protective apron.

In the embodiment of FIGS. 20A and 20B, the annular protection piece 33 can be fixed directly to the collar 26 of the support member 22 in the form of a backpack 40. This support member 22 in the form of a backpack back 40 comprises two shoulder straps 41 and at least one hip strap 39. The height of the support member 22 comprising a backpack 40 is advantageously adjustable by means of a sliding and lockable plate 42. This allows to best adjust the height according to the user and thus perfectly position the hood as well as the hip straps, and this for all sizes and morphologies of users. As shown in Figures 18 and 19, the annular base 1 provided with the hood 5 and the ventilation system 2 can in turn be slipped around the user's head. During this operation or when fixing the base on the support member, detection means can automatically trigger the implementation of the compressor and therefore the circulation of air in the respirator.

It should be understood that the foregoing description has been given on a non-limiting basis and that many variants or modifications may be provided without departing from the scope of the appended claims.

It is possible, for example, to provide that the support member is formed of two half-parts in the form of a breastplate on each of which is arranged in a fixed manner a half-part in the form of a collar. These two support member halves can then be joined together by appropriate means around the neck of the user.

It is also possible to plan to test the purifying respirator before it is put into service. As illustrated in Figure 5, a tester member 37 is mounted on the underside of the annular base 1, fitted with the hood 5 and the ventilation system 2, so as to ensure the tightness of the respirator. This tester unit further comprises in particular means for operating the compressor, possibly charging the battery, determining the condition of the filters of the filtering cartridge, checking the correction of the air flow through the respirator, etc.

Claims

1 . Air-purifying respirator comprising: i) an annular base (1), which has a central opening allowing free passage for a user's head and means for receiving a hood (5), this annular base having a front part and a back part, opposite the front part, ii) a hood (5) adapted to be supported by said annular base (1), said hood forming an at least partially transparent hollow body having an interior volume in which said head of user can be accommodated in a freely movable manner and comprising at least one rigid part which can be detachably connected with the ring base, and iii) a ventilation system (2) mounted on said dorsal part of the base annular and forming with this base a circuit for supplying fresh filtered air to the hood and a circuit for evacuating filtered used air from the hood, said supply circuit connecting a fresh air inlet (12) disposed on said ventilation system (2) to a fresh filtered air supply (13) provided on said base (1) and comprising an inlet filtering element (9) disposed at said fresh air inlet, said circuit evacuation connecting a used air exhaust (16) provided on said base (1) to a filtered used air outlet (17) arranged on said ventilation system (2) and comprising an outlet filter element (10 ) to said filtered used air outlet, said filtered fresh air supply (13) and said used air exhaust (16) being in fluid communication with said interior volume of the hood, said fresh air supply circuit filtered being provided with a compressor (1 1) arranged to draw off surrounding air through the inlet filter element (9).

2. Air-purifying respirator according to claim 1, wherein said filtered used air evacuation circuit is provided with an additional compressor which is arranged to draw used air out of the hood through the outlet filter element (10).

3. Air-purifying respirator according to either of claims 1 and 2, wherein the evacuation circuit is equipped with a flow measurement element (21) arranged to measure the flow at the outlet used air and adjust the compressor (1 1) so that the flow rate at the outlet of the used air is at all times positive with respect to the pressure at the fresh air inlet (12).

4. Air-purifying respirator according to any one of claims 1 to 3, wherein the annular base (1) comprises an upper face carrying said hood receiving means and a lower face, said upper face comprising a peripheral surface (3), an annular shoulder (4) projecting upwards, arranged to center said hood (5) when the latter is placed on the base, and an internal peripheral surface (6), said surface external peripheral (3) being arranged to form a support for the hood.

5. Air-purifying respirator according to claim 4, wherein the hood (5) has a front part to be placed facing the user and in that the inner peripheral surface (6) of said annular base (1) comprises, as a supply of the aforesaid filtered fresh air into the hood, one or more orifices (17) in the front part of the base to form a curtain of fresh air rising along the said front part of the hood, the interior of it.

6. Air-purifying respirator according to any one of the preceding claims, in which the hollow body of the hood (5) has a periphery and a transparent wall over at least 65% of this periphery.

7. An air-purifying respirator according to any preceding claim, wherein the hood (5) is fully rigid.

8. Air-purifying respirator according to any one of the preceding claims, comprising one or more control means chosen from load control means of an energy source (15) for said compressor (1 1) and of other electrically operated elements, filter element quality control means, hood leak control means, means for detecting the mutual engagement between the hood and the annular base.

9. Air-purifying respirator according to claim 8, further comprising, on the annular base (1), in the front part thereof, one or more indicators (18,19) connected to said control means and arranged to emit a light and/or sound signal in response to a signal from the control means.

10. Air-purifying respirator according to one of Claims 8 and 9, further comprising one or more control means (20) of the circulation of air in the aforementioned supply and evacuation circuits, which are provided on the annular base, in the front part thereof, and are manually operable, and/or which react to signals originating from said detection means.

1 1. Air-purifying respirator according to any one of the preceding claims, further comprising a support member

(22) to be arranged on the shoulders and/or the thorax of the user and intended to be detachably connected to said annular base (1) on which said hood (5) can be mounted.

12. Air-purifying respirator according to claim 11, in which the support member (22) comprises a portion in the form of a breastplate

(23) to be fixed on the user's shoulders and/or thorax and a neck part (25) having a central opening allowing the user's head to pass freely, the neck part being supported by the in the form of a faceplate and being provided with a flange (26) projecting outwardly having an upper surface, this upper surface and the said lower face of the annular base having fixing means (27) allowing centered mutual engagement and detachable.

13. An air-purifying respirator according to claim 12, wherein said securing means (27) includes centering pins projecting upwardly from the upper surface of the collar and locking holes for receiving these pins. , in the underside of the annular base.

14. Air-purifying respirator according to either of claims 12 and 13, comprising, in the engagement position of said upper surface of said collar (26) and of said lower face of said annular base (1) by said fixing means (27), a washer (30) of flexible material which is inserted between said upper surface and said lower face, is traversed by the fixing means (27) and has an internal peripheral edge (31) projecting inwardly from the neck portion (25) of the support member (22).

15. Air purifying respirator according to claim 14, wherein the washer (30) of flexible material is provided with a drawstring (32) allowing tightening of the inner peripheral edge (31) of said washer around the neck of the user.

16. Air-purifying respirator according to any one of claims 12 to 15, in which the part in the form of a plastron is provided with a sealed internal padding (39), which isolates the hollow volume of the hood (5) from the outside.

17. Air-purifying respirator according to any one of claims 12 to 16, comprising, in the engagement position of said upper surface of said collar (26) and of said lower face of said annular base (1) by said means (27), an annular protective piece (33) of flexible material which is inserted between said upper surface and said lower face, is traversed by the aforementioned fixing means (27), and has a covering part (36) which protrudes outward at least partially covering the support member (22).

18. Air-purifying respirator according to claim 17, in which the annular protective part (33) is provided with a tightening link (35) allowing said covering part (36) to be tightened around said collar part. (25) of the support member (22).