Respiratory air disinfection device, respiratory protection mask with it and respiratory air disinfection procedure with it

Description

[0001] The invention relates to a breathing air disinfection device with a breathing air duct through which breathing air is supplied to and / or extracted from a person via an inlet section in a first flow direction, wherein a widened section of the breathing air duct is provided and UVC radiation media for disinfecting the breathing air are arranged in the widened section of the breathing air duct. The invention further relates to a respiratory mask with such breathing air disinfection devices and a breathing air disinfection method therein.

[0002] The first flow direction of the breathing air is to be understood as a general flow direction that leads towards or away from a person along the longitudinal axis of the breathing air channel, which is designed, for example, as a breathing air hose or the like.

[0003] US Patent 2016 / 0001108 A1 discloses a breathing air disinfection device that incorporates UV irradiants in a flow chamber, disinfecting the air flowing through it. The breathing air is passed through a flow chamber and swirled by structures within it, effectively lengthening the airflow path. Alternatively, the flow chamber is divided into several serpentine breathing air channels, which lengthen the air path and thus improve air purification.

[0004] The subsequently published DE 10 2020 106 235 B3 describes a respiratory mask in which breathing air is guided through an interior chamber containing ultraviolet-emitting light sources. The interior chamber can be divided into two chamber sections by means of a separating device, with the chamber sections being fluidically connected.

[0005] From US patent 2019 / 0117820 A1, a personal air treatment device is known, which is to be used in particular together with a particle mask, wherein the air treatment device includes an LED UV light source for air treatment.

[0006] Furthermore, US Patent 2015 / 0359921 A1 describes an air purification system for buildings in which outside air is drawn in by a fan and passed through an irradiation chamber with a germicidal UV light source. In a particular embodiment, a deflector plate is designed as a flat plate with gaps along its edges through which the incoming air is directed. Behind this flat plate, a perforated plate is arranged to shield the UV radiation acting within the UV chamber.

[0007] Based on US 2015 / 0359921 A1, the object of the invention is to provide a breathing air disinfection device or method with which reliable and energy-efficient disinfection of the breathing air is possible.

[0008] This problem is solved with a respiratory air disinfection device according to claim 1 and a respiratory air disinfection method according to claim 8.

[0009] Because the widened section of the breathing air duct has an all-round widening in all radial directions, with a flow surface in the area of ​​the greatest widening that hinders the straight-line flow of the breathing air and causes the breathing air to be deflected in all radial directions towards the first outward flow direction in this widened section of the breathing air duct, and because the effective flow cross-section in the widened section is thus wider than the flow cross-section in the inlet section, the flow path of the breathing air in the device is lengthened and at the same time the flow cross-section in this widened section of the breathing air duct is increased.

[0010] Crucially, the breathing air, which flows in the original first flow direction (general flow direction), is now deflected in all radial directions, i.e., now fanned out over the entire circumferential direction around the first flow direction, is deflected into a further, namely deflected, flow direction as the radial flow direction, whereby the effective flow cross-section is divided over the entire circumference times the width of this area and increases significantly in the radial direction outwards with the increasing radius.

[0011] Accordingly, the airflow through this widened section of the breathing duct is slowed down, and the path it travels through this widened section is lengthened. As a result, the exposure time is extended, and the effect of the UVC radiation on the air flowing through this widened section and any germs it may contain is significantly improved. It should be noted that UVC light is already considerably attenuated in air, meaning it only penetrates a few millimeters to 10-20 mm. Furthermore, any intervening layers can cause an additional, significant reduction in radiation intensity.

[0012] Furthermore, it should be considered that an average adult at rest inhales approximately half a liter of air per breath over a period of about 1.5 seconds. This results in a flow velocity of approximately 2 m / s for a typical air supply tube, such as those used in hospitals, with an inner diameter of 15 mm. By widening the flow cross-section in the broadened section of the air channel, a significantly reduced velocity of a few cm / s, preferably 1 cm / s or even less, is achieved in the outer periphery, depending on the geometric design. For this purpose, the effective flow cross-section in the broadened section is increased by a factor of 10 to 500, preferably by a factor of 20 to 100, compared to the flow cross-section in the inlet section.

[0013] The widening on all sides takes the form of a cylinder, with the cylinder axis coinciding with the first flow direction and the flow surface being a circular disk positioned centrally and orthogonally to the first flow direction within the cylinder, leaving an annular space between the cylinder's surface and the circular disk for further flow deflection. This further flow deflection occurs in the annular space near the outer edge of the circular disk, so that the breathing air—at an even reduced flow velocity—already flows out in the direction of the first flow direction.Depending on the design of the breathing air disinfection device and the further flow of the breathing air, in one embodiment the breathing air can be brought together again in a narrower single breathing air tube as a continued breathing air channel, which increases the flow velocity of the breathing air again, or the breathing air is deflected directly or radially slightly inwards at this point in the annular space between the cylindrical surface and the circular disc, for example into a breathing mask.

[0014] The formation of the all-around expansion in the form of a cylinder is very easy to manufacture and allows for a largely uniform distribution of the breathing airflow within this widened section of the breathing air duct. Accordingly, a substantially uniform reduction in flow velocity and distribution of the breathing air within this cylinder should result. Due to the extended flow path also achieved in this way, a significantly increased exposure time of the UVC irradiation to the passing breathing air can be achieved.

[0015] The UVC emitters are positioned in the widened section, in the area of ​​greatest flow cross-sectional expansion. This ensures that the UVC irradiation takes effect in the area of ​​slowest airflow, resulting in particularly high efficacy. Considering the extended flow path, the slower airflow, and the possibility of placing the UVC emitters directly at the periphery of this widened section of the breathing air duct, efficient exposure times of 2-3 seconds for UVC irradiation of an air particle flowing past can be achieved. It has been observed that exposure times exceeding 1 second, when using conventional UVC LEDs with, for example, 0.6 watts of power, result in very effective germ reduction, specifically the killing of any airborne bacteria, viruses, or similar pathogens.

[0016] This task is accomplished by the following steps: The breathing air is redirected in all radial directions towards the first outward flow direction in a widened section of the breathing air duct, thereby increasing the flow path and cross-sectional area in this widened section. The breathing air in this widened section is then irradiated with UVC radiation, with the UVC radiation being applied to the air at the radially outer edge in the area of ​​greatest expansion of the cross-sectional area. This ensures highly effective disinfection in this area of ​​lowest airflow velocity.

[0017] When the breathing air is deflected back into the general flow direction at the radial outer edge in this widened section of the breathing air channel, the breathing air can be further guided to a breathing mask via appropriately connected hoses, again with the significantly higher airflow velocity that develops therein.

[0018] Alternatively, for example, two air disinfection devices can be arranged directly in a respiratory mask, whereby a redirection back to the general flow direction of the breathing air is dispensed with and the disinfected breathing air can be directed directly into the interior of the breathing mask.

[0019] Furthermore, the UVC irradiation can be modulated and / or summed to achieve a better penetration depth of the UVC radiation in the air to be disinfected. This is intended to counteract the attenuation of the UVC radiation in the air and ensure an enhanced effect. A technique already known from radio communication or the modulation of infrared or laser light can be used for this purpose. Both amplitude and frequency modulation are possible. Additionally, summed signals with a UVC-enhancing effect can be generated by adding one or more further light frequencies.

[0020] To support a uniform flow distribution, flow guide surfaces are provided in the breathing air duct and especially in the widened section of the breathing air duct, which divide the flow of breathing air into similar flow paths.

[0021] If the widened section of the breathing air duct is made of a UVC-transparent material, such as crystal glass or graphene, particularly plastic, preferably PMME, and UVC LEDs are arranged on it as the UVC radiation source, the UVC LEDs can also be positioned on the outside of the housing. Alternatively, however, the UVC radiation source in the form of UVC LEDs can also be arranged inside the breathing air duct in the widened section, since in this case direct irradiation of the flowing breathing air is possible without having to consider the intensity of the UVC irradiation due to intensity-reducing interface transitions.

[0022] By positioning a liquid separator and / or a particle filter in the breathing air duct, upstream of the widened section, undesirable components, namely excessive moisture and any dirt / dust particles, can be filtered from the breathing air. This is advantageous for hygienic reasons, as bacteria / viruses often adhere to moisture droplets and / or particles, and contamination of the interior of the breathing air disinfection device must be avoided.

[0023] If an ultrasonic transducer is located on the widened section, cleaning cycles for the breathing air disinfection device can be performed by activating the transducer. These cycles remove any dirt / dust particles within the device, particularly in the widened section. This can be done at separate service intervals or periodically during normal operation.

[0024] Two exemplary designs are described in detail below with reference to the accompanying drawings.

[0025] It shows: Fig. 1 a breathing air disinfection device in a first embodiment in a partially cutaway view, Fig. 2 the in Fig. 1Fig. 3 shows a cross-section of the breathing air disinfection device, Fig. 3 shows a spatial view of a second embodiment of the invention in the form of a respiratory mask with two breathing air disinfection devices, and Fig. 4 shows a partially cutaway view of one side of the device. Fig. 3 depicted respirator mask.

[0026] In Fig. 1 A breathing air disinfection device in a first embodiment is shown in a partially cutaway view. Fig. 2 This air disinfection device is shown in cross-section. It is shown in Fig. 2 a breathing air channel 1 with a small diameter inlet section 11, a widened section 2 with a significantly larger diameter (see Fig. 1 ) and an outlet section 12 is again shown with a small diameter.

[0027] In the embodiment shown here, the widened section 2 of the breathing air duct 1 is cylindrical or can-shaped, thus having a relatively small cylinder height H and a relatively large cylinder diameter. Arrows indicating the corresponding flow directions are shown to clarify the flow path for the breathing air guided through the breathing air duct 1. The widened section, or the widening on all sides 2, here in cylindrical form, has a cylinder axis 21 that coincides with the first flow direction X, and a flow surface in the form of a circular disk 22 is arranged within the widened section 2 in cylindrical form. The widened section 2 is formed from a cylindrical housing 20.In the inlet section 11, the breathing air flows with a first flow direction X parallel to the longitudinal extent of the breathing air channel 1 (along the cylinder axis 21 of the corresponding pipe sections) and then divides into second flow directions R, radial to the first flow direction X, whereby the breathing air flow is distributed in the widened section 2, which is designed as an all-round widening in cylindrical form, as indicated by the flow arrows there labeled R.

[0028] In the partially cropped view according to Fig. 1 It can be seen that in the widened section 2, flow guide surfaces 23 are arranged in a cylindrical shape such that the widening cavity inside the cylinder is divided into eight equally sized sectors 24. These pie-shaped sectors 24 can be further subdivided in the outer peripheral area by air guide walls 25, which complement the flow guide surfaces 23.

[0029] In Fig. 1In the partially cutaway view, the circular disk 22 is shown in plan view. An annular space 27 is formed between the outer circular edge of the circular disk 22 and the circumferential cylindrical surface 26 of the housing 20, through which the breathing air flows around the circular disk 22, as shown in Fig. 2 It can be seen that the flow is deflected back to the cylinder axis 21 in cylinder 2 and subsequently to the outlet section 12 of the breathing air channel 1, back into the first flow direction X.

[0030] Furthermore, in Fig. 1 UVC radiation medium 3 in the form of UVC LEDs 31 is shown on the inner surface of the cylindrical lateral surface 26. In the embodiment shown here, one UVC LED 31 is provided for each sector 24, as is also the case in Fig. 2as shown above. If necessary, further UVC LEDs 31, particularly in the peripheral area, i.e., close to the outer edge of the cylindrical, all-around widening 2, can be arranged in the housing 20 of the widened section 2, as shown in Fig. 2 shown below as an alternative.

[0031] The following section refers again to the flow path representation according to Fig. 2The breathing air flowing in via inlet section 11 in the direction of the first flow direction X is forcibly deflected in radial flow direction R in all radial directions towards the first flow direction X by the circular disk 22 arranged in the widened section 2. Accordingly, the breathing air spreads out into fan-like flows in the eight sectors 24 across the entire circumference. This fan-like widening across the entire circumference results in an increase in cross-sectional area compared to the diameter of the inlet section 11, and, with a corresponding effective height H of the cylinder 2, a significant reduction in the overall flow velocity, as illustrated by the shorter flow arrows at the peripheral edge.

[0032] The UVC radiation sources 3, preferably in the form of individual UVC LEDs 31, are preferably arranged precisely at this point (at the periphery or outer edge of the cylinder 2). For example, the UVC LEDs 31 can be arranged on the inside of the cylinder's outer surface 26 to shine directly onto the incoming breathing air. Optionally, additional UVC LEDs 31 can be arranged on the housing 20 of the cylinder 2, particularly in the cylinder lid 201 of the housing 20, again close to the outer periphery. Commercially available 0.8-watt LEDs, for example, can be used as UVC LEDs 31. Such UVC LEDs 31 have a light intensity in the UVC range suitable for killing microorganisms, especially bacteria, viruses, or the like, with a penetration depth of this UVC radiation into the airspace of at least 10 mm, preferably at least 20 mm. Accordingly, in Fig. 2An effective space 32 is shown with a dashed line, in which the UVC radiation emitted by the UVC LED 31 has a germicidal effect.

[0033] Due to the significant cross-sectional expansion in the area of ​​the widened section or cylinder 2, the flow velocity decreases in proportion to this increase in cross-sectional area. Because of the extended flow path in this widened section 2 and the optimal coupling of the UVC irradiation by the UVC radiation source 3 in the area of ​​lowest possible airflow velocity, namely near the outer edge of cylinder 2, the UVC radiation exerts a sufficiently germicidal effect over a range of 20 to 40 mm. With the use of two UVC LEDs 31 per sector 24, this effect is likely to extend up to 60 mm. Thus, the slowly flowing air through this area is disinfected with high efficiency due to the germicidal properties of the UVC radiation. Exposure times of at least one second, but most likely several seconds, per passing air particle should be achievable.

[0034] Accordingly, the number of germs is drastically reduced, meaning that the air being breathed in the area of ​​outlet section 12 is practically germ-free.

[0035] The widening (enlargement) of the flow cross-section in the airway (breathing air duct 1) can be seen in the Figs. 1 and 2 The illustrated embodiment can be calculated from the cylinder circumference multiplied by the effective cylinder height in relation to the cross-section of the supply hose (inlet section 11), for example with rs = radius of inlet section 11, e.g. 7.5 mm, r Z = 5 * rs = radius of cylinder 2, h Z = 2 * * rs = effective cylinder height, i.e., distance between cylinder head 201 and circular disk 22, v 1 = 2 m / s = flow velocity in inlet section 11 and v 2 = resulting flow velocity near the outer edge of the cylinder surrendered: π * rs 2< * v 1 = 2 * π * r Z * r Z * v 2 rs 2< * v 1 = 2 * 5 * rs * 2 * rs * v 2 so: v 2 = 1 / 20 * v 1 , This reduces the flow velocity, which is, for example, 2 m / s at the inlet section, to 1 / 20 of the flow velocity, i.e., 0.1 m / s, near the outer edge of the cylinder. And it is precisely at this point that the UVC LEDs should be positioned for optimal effectiveness, as shown in the dashed-dotted area 32 in [reference missing]. Fig. 2 This illustrates the point. The air flows here at a relatively slow speed of 10 cm / s over an effective area of ​​several centimeters, so that the air flowing along this area is exposed to intense UVC radiation for approximately 0.5 seconds.

[0036] In a second embodiment according to the Figs. 3 and 4 A respiratory mask 4 is equipped with two breathing air disinfection devices, such as those used in the Figs. 1 and 2 described, illustrated. In Fig. 3 The respiratory mask 4 is shown in a three-dimensional view. From Fig. 4, in which a partially cut-out partial view of the respiratory mask 4 according to Fig. 3 The diagram illustrates the flow path of the breathing air through the respective breathing air disinfection device. In this second embodiment, functionally identical components to those in the first embodiment are identified with the same reference numerals.

[0037] In contrast to the first embodiment, the breathing air is introduced freely into the respirator 4 immediately after passing the circular disc 22. This advantageously introduces the breathing air into the interior of the respirator 4 at a low flow velocity, so that hardly any unpleasant air currents are noticeable on the facial skin and there is also hardly any turbulence within the respirator 4. The respirator 4 has an airtight mask body 40 to which the two breathing air disinfection devices are attached according to the Figs. 1 and 2are inserted. In this embodiment, a fine dust filter 41 is arranged at the free end of the inlet section 11. Furthermore, an exhalation valve 42 is housed in the airtight mask body 40, so that the exhaled air can be released directly into the environment via this exhalation valve 42, acting as a non-return valve. Optionally, sensors can be provided in both air disinfection devices to monitor the distribution of the airflow. Alternatively, the exhaled air can also be passed back through the air disinfection devices to disinfect the exhaled air released into the environment, particularly in the case of infected individuals.

[0038] As a further option, an ultrasonic transducer 28 can be provided on the breathing air disinfection device, particularly on the widened section / cylinder 2. When activated, the ultrasonic transducer 28 causes cleaning of dust / dirt particles in the area of ​​the breathing air duct 1, particularly on the widened section / cylinder 2, by means of the vibrations generated by it. This cleaning can be carried out at predetermined time intervals or in a service mode to ensure optimal effectiveness of the UVC irradiation and simultaneously maintain hygienic internal surfaces in the breathing air disinfection device.

[0039] Another way to increase the efficiency of UVC irradiation is to modify UVC light by modulating the amplitude or frequency and / or to superimpose the UVC light with one or more light sources with different frequencies in order to obtain a sum light signal in the UVC range that has a higher effect and possibly less attenuation in the air and possibly in the UVC-transmitting material of cylinder 2.

[0040] The UVC light modulation with a carrier frequency promotes transmission through the air. This UVC irradiation leads to demodulation upon the presence of specific crystalline surfaces / structures, allowing it to exert its UVC effect again. These crystalline structures for demodulation can be arranged in the housing 20 of cylinder 2 to enhance the disinfection effect and counteract attenuation by the air and, if applicable, by the UVC-transmitting material of cylinder 2. Reference symbol list

[0041] 1 Breathing air duct 11 Inlet section 12 Outlet section 2 Widened section, all-round widening, cylinder 20 Housing 201 Cylinder cover 21 Cylinder axis 22 Flow surface, circular disk 23 Flow guide surface 24 Sector 25 Air guide wall 26 Cylinder shell surface 27 Annular space 28 Ultrasonic transducer 3UVC radiation medium 31UVC LED 32Effective area 4 Respirator 40 Airtight mask body 41 Fine dust filter, particle filter 42 Exhalation valve HH Height of the cylinder R Radial flow direction X First flow direction

Claims

1. Respiratory air disinfection device having a respiratory air channel (1), through which respiratory air is conducted to and / or from a person via an inlet portion (11) in a first direction of flow (X), wherein a widened section (2) of the breathing air channel (1) is provided and UVC radiation means (3) for disinfecting the breathing air are arranged in the widened section (2) of the breathing air channel (1), wherein the widened section (2) of the breathing air channel (1) widens omnidirectionally in all radial directions (R) , wherein in the area of the greatest widening a flow surface (22) is provided which prevents the breathing air from flowing through in a straight line and which causes deflection of the breathing air in all radial directions (R) to the first flow direction (X) outwards in this widened section (2) of the breathing air duct (1), the effective flow cross-section in the widened section (2), compared to the flow cross-section in the inlet section (11), is enlarged by a factor of 10 to 500, wherein the UVC radiation means (3) are arranged in the widened section (2) in the area of the largest flow cross-section expansion and the omnidirectional expansion has the shape of a cylinder (2), wherein the cylinder axis (21) of the cylinder (2) coincides with the first flow direction (X) and the axis of the inlet section (11), and the flow surface is a circular disc (22) which is arranged centrally and orthogonally to the first flow direction (X) in cylinder (2) in such a way that an annular space (27) remains free at the outer edge between cylinder housing surface (26) and circular disc (22) for further flow deflection.

2. Respiratory air disinfection device according to claim 1, characterized in that the effective flow cross-section in the widened section (2), compared to the flow cross-section in the inlet section (11), is increased by a factor of 20 to 100.

3. Respiratory air disinfection device according to any one of the preceding claims, characterized in that baffle surfaces (23) are provided in the widened section (2) of the respiratory air channel (1), which divide the flow of the respiratory air to equal flow paths.

4. Respiratory air disinfection device according to any one of the preceding claims, characterized in that the widened section (2) of the respiratory air channel (1) is formed from a UVC light-transmitting material on which UVC LEDs (31) are arranged as UVC radiating means (3).

5. Respiratory air disinfection device according to any one of the preceding claims, characterized in that a liquid separator and / or a particle filter (41) is arranged in the respiratory air channel (1) in front of the widened section (2) in the direction of flow of the respiratory air.

6. Respiratory air disinfection device according to any one of the preceding claims, characterized in that an ultrasonic transducer (28) is arranged on the widened section (2).

7. Respiratory protection mask (4) with at least one respiratory air disinfection device according to one of the preceding claims.

8. Respiratory air disinfection method by which respiratory air is supplied and / or discharged via a respiratory air channel (1) in a first direction of flow (X) to a person, wherein the respiratory air flowing in the respiratory air channel (1) is exposed to UVC radiation, with the steps: - redirecting the respiratory air in all radial directions (R) to the first flow direction (X) outwards in a wider section (2) of the respiratory air channel (1), whereby the flow path and the flow cross-section in this widened section (2) of the respiratory air channel (1) increase and - irradiating the respiratory air in this widened section (2) of the respiratory air channel (1) with UVC radiation, wherein the respiratory air is exposed to UVC radiation at the radial-outer edge in the area of the largest expansion of the flow cross-section.

9. Respiratory air disinfection method according to claim 8, characterized in that the respiratory air at the radial-outer edge in this widened section (2) of the respiratory air channel (1) is redirected back to the first flow direction (X).

10. Respiratory air disinfection method according to claim 8 or 9, characterized in that the UVC radiation is modulated in the radiation frequency.

11. Respiratory air disinfection method according to claim 8, 9 or 10, characterized in that the UVC radiation is summed.