Dynamic filtering device for aeraulic apparatuses of passenger transport vehicles

Abstract

A dynamic filtering device for aeraulic apparatuses of passenger transport vehicles, comprising active filters of the photoreactive type.

Description

[0001] DESCRIPTION

[0002] Title

[0003] DYNAMIC FILTERING DEVICE FOR AERAULIC APPARATUSES OF PASSENGER TRANSPORT VEHICLES

[0004] Technical field

[0005]

[0001] The present invention belongs to the field of air filtration systems that are part of vehicles for the collective transport of people, especially railway, tram, subway, and similar vehicles.

[0006]

[0002] In particular, the invention concerns a filtering device comprising so-called active filters, configured to be easily installed on vehicles already in operation and equipped with specific functionalities for optimal maintenance management. More precisely, the present invention relates to a filtering device comprising means for real-time monitoring of its efficiency status and for scheduling its maintenance based on actual cleaning, replacement, etc., needs.

[0007]

[0003] It is specified that in this patent text, references to rolling stock and to railway and tram carriages in general are not to be understood in a limiting sense, as the invention can find direct application on any other type of transport vehicle equipped with a ventilation system, as well as in environments not necessarily in motion, such as, for example, schools, offices, or hospitals.

[0008] Present status of the art

[0009]

[0004] Transport vehicles are generally equipped with aeraulic ventilation systems, which, especially in railway and tram vehicles, comprise air treatment apparatuses that both control the air temperature when it's introduced into the carriages and integrate recirculated air with fresh air drawn from outside the vehicle.

[0010]

[0005] These apparatuses, currently referred to as air handling units (AHUs), draw air from the outside through an intake grille which typically includes at least one active high-efficiency filter. The term "active filter" refers to a device that, in addition to being configured to retain micro and nanoparticles from the air passing through it, includes further technologies that help it capture a greater number of micro and nanoparticles, thus making the filtration itself more effective; traditional filters, lacking these technologies, are called static filters.

[0011]

[0006] In certain cases, these active filters not only increase particle capture capacity, for example with electrostatic systems, but also contribute to destroying pathogenic micro or nanoparticles such as bacteria and viruses by means of ultraviolet irradiation systems. For example, Italian patent application 202024000002341 describes filters comprising a three- dimensional polymer lattice where the surface in contact with the airflow has been at least partially coated with Titanium Dioxide and / or Silver and is irradiated by UV-C ultraviolet light emitted by one or more LED lamps. The presence of the three-dimensional lattice ensures high filtering efficiency while maintaining sufficiently wide passage sections to not obstruct the airflow; furthermore, passing through the three-dimensional lattice increases the air's dwell time within the filter, thereby increasing its exposure to the virucidal action of photocatalysis.

[0012]

[0007] Photoreactive active filters, with their bactericidal and virucidal effect, offer several advantages, firstly because their effectiveness doesn't depend solely on the quantity of particles they can physically retain, and they can be configured so as to cause a lower pressure drop in the aeraulic circuit than traditional static filters; secondly because their virucidal action renders harmless pathogenic agents that progressively come to be retained within them, providing clear benefits for both disposal and the safety of maintenance personnel. Furthermore, to reduce pressure drops without diminishing the overall effectiveness of the filtering apparatus, the adoption of so-called "pre-filters" is known, possibly combined with devices capable of creating an electrostatic barrier that can electrically attract micro and nanoparticles.

[0013]

[0008] Nonetheless, active filters also present some disadvantages: for example, they are intrinsically quite expensive, they consume a significant amount of energy, as they must power the UV lamps that emit the ultraviolet light required for the bactericidal and virucidal photoreaction, moreover in some instances they generate harmful byproducts and possess dimensions that only permit their installation in newly built air conditioning systems specifically engineered to accommodate their substantial size, weight, and energy absorption. Furthermore, the diagnostic system that detects their operation and effectiveness must necessarily be included in the vehicle's system from the time of its manufacture. As a result, all rolling stock already in operation is excluded from using active filters, as its adaptation would be uneconomical and would, in any event, involve a period of vehicle unavailability so prolonged that it could not be considered.

[0014]

[0009] It is known that filters gradually become soiled by impurities conveyed in the air that passes through them and consequently they must be periodically cleaned to eliminate the polluting and harmful material they have retained internally before they reach saturation.

[0015]

[0010] In operational practice, filters undergo a certain number of cleaning cycles, after which they need to be replaced with new ones; normally, these operations are staggered based on the time elapsed since the previous operation, without taking into account the filter's actual maintenance state or its real efficiency, the latter in fact depends on many variables, such as the correct functioning of the LED lamps that emit ultraviolet light.

[0016] [Oil] Solutions to the problem of maintenance frequency have been developed, such as those described in US10363510B1, US2019 / 263226A1, and US11517841B2.

[0017] Objects and summary of the invention

[0018]

[0012] The purpose of the present invention is to provide a filtering device comprising a three-dimensional active filter with a surface coating of biocidal reagents, irradiated by UV- C LEDs interfaced with electronics capable of dynamically regulating the intensity of the latter in relation to the actual airflow, and completed by a plurality of sensors that detect its actual operating conditions in real time.

[0019]

[0013] At the same time, a further aim of the invention is to provide a filtering device of compact dimensions and reduced energy consumption, which is easily interchangeable with the static filters equipping the majority of the existing rolling stock, and whose control system is independent of the command and control systems already present on board the vehicles in operation. The filtering device of the present invention comprises at least one photoreactor filter with virucidal efficacy, innovative for use in the ventilation systems of transport vehicles, particularly railway and tram vehicles, and it can be inserted into the filtering apparatuses by placing it either in the air treatment units or upstream of the diffusers, thereby combining high filtering efficacy with strong virucidal and bactericidal properties, all without imposing excessively high pressure drops on the aeraulic circuit and without producing harmful substances.

[0020]

[0014] A further aim of the present invention is to provide a filtering device whose filters do not need to be disposed of as polluting or hazardous waste, but rather can be easily reconditioned for reuse over a certain number of subsequent filtration cycles.

[0021]

[0015] It is known that to ensure adequate comfort for passengers, the airflow passing through the filtering apparatuses is, on average, composed of approximately 30% external air and 70% internal air, specifying that this proportion can vary to take into account the respective temperatures of the external and internal air. Advantageously, the filtering device of the present invention allows for considering the actual flow rate of the gaseous fluid passing through it and consequently for regulating the virucidal irradiation of the UV-C LED lighting bodies that emit the ultraviolet light necessary for the photoreaction.

[0022]

[0016] Thanks to this regulation, it's possible to achieve significant electrical energy savings and an appreciable extension of the lifespan of the lamps, particularly the costly UV-C LEDs.

[0017] Another, equally important, aim of the present invention is to provide a filtering device where the main operating parameters are detected by dedicated sensors, interfaced with an electronic control unit that, in addition to providing feedback for the virucidal light irradiation, can store data and communicate it to the vehicle's maintenance services, whether on-board or ground-based, operating independently of the electronics already installed on board, simply by preparing a log file and sending it to a device used by the personnel responsible for operating the vehicle.

[0023]

[0018] The log file can be transmitted either via cable or wirelessly.

[0024]

[0019] These and other aims are achieved by a filtering device as described and claimed hereafter, which comprises one or more filters including a three-dimensional lattice, preferably made of polymeric material, where the surface coming into contact with the airflow has been at least partially coated with Titanium Dioxide and / or with Silver and is irradiated by UV-C ultraviolet light emitted by one or more LED lamps.

[0025]

[0020] The presence of the three-dimensional lattice ensures high filtering efficiency while maintaining sufficiently wide passage sections to not obstruct the airflow; furthermore, passing through the three-dimensional lattice increases the air's dwell time within the filter, thus increasing its exposure to the virucidal action of photocatalysis.

[0026]

[0021] The following description and the accompanying drawings refer, merely by way of example and not exclusively, to a ventilation apparatus with at least one filtering device comprising: at least one three-dimensional virucidal filter (4, 5), with surfaces at least partially coated with photoreactive material, such as, for example, Titanium Dioxide and Silver, and irradiated by UV-C LEDs; at least one electronic control unit (12) for processing the diagnostic parameters and for powering and controlling the radiation emitted by the UV-C LEDs, varying their emissions according to the actual airflow; said control unit being telematically interfaceable with customer's maintenance equipment, both on board the vehicle and in the workshop; at least one anemometric device, interfaced with said electronic control unit, for detecting the fluid dynamic pressure drop imposed by the filter on the gaseous flow passing through it; at least one limiter of electrical power supply surges; at least one sensor for detecting the intensity of the UV-C LEDs, interfaced with said electronic control unit, to verify their effectiveness and thus the proper sanitization of the filter.

[0027]

[0022] According to a particularly effective embodiment, the ventilation apparatus comprising the filtering device subject of the present patent includes a pre-filter capable of creating an electrostatic barrier.

[0028]

[0023] To facilitate the exchange of information between the control unit and the customer's maintenance equipment, the filtering device subject of the present invention can include means of radio communication.

[0029]

[0024] Advantageously, the invention can also include at least one thermal sensor for verifying the actual operating temperature.

[0030]

[0025] Preferably, the polymeric material used for constructing the three-dimensional filters belongs to the polyester category, or other polymeric materials characterized by high chemical resistance, good performance even at high temperatures, self-extinguishing properties, and rapid molding and / or ease of weaving. In particular, it's preferable to adopt a polymeric material suitable for molding with layering technology.

[0031]

[0026] A different, particularly suitable, constructive solution involves the polyester being woven so as to create a three-dimensional lattice between two external porous surfaces and with various subsequent immersion and chemical-thermal fixation processes; alternatively, treatments with plasma systems in air can be used, by means of which nanoparticles of both Titanium Dioxide and Silver are fixed onto the external surfaces and the internal lattice of said fabric, with the thickness of the nanoparticle layer varying from a few nanometers to several tens of nanometers, depending on the required durability and effectiveness.

[0032]

[0027] Preferably, the filtering device of the present invention is enclosed in a protective casing to prevent air leakage from the apparatus, which would result in air flow rate losses and air flow speed variations, and also to protect human eyes and skin from UV-C ultraviolet radiation.

[0028] A further aim of the present invention is to provide a filtering apparatus for a ventilation system, especially suitable for the treatment and exchange of air in passenger transport vehicles, comprising at least one air treatment unit (1), a branched ducting (2) that delivers the air exiting said treatment unit up to one or more diffusers (3), including at least one filtering device as described and claimed herein.

[0033] Brief description of the drawings

[0034]

[0029] Fig. 1, 2, and 3 show views of the filter.

[0035]

[0030] Fig. 4 shows a detailed view of the control unit (12) and the radio transmission system (13).

[0036]

[0031] Fig. 5 shows an air treatment unit (1), constructed according to the prior art, including a virucidal photoreactor filter (10), which introduces treated air into a ducting (2) that delivers it to one or more diffusers (3).

[0037]

[0032] Fig. 6 shows an air treatment unit (1) that provides for filtering the air to be treated with a first virucidal photoreactor filter (4) as it enters the air treatment unit (1) and also provides for treating the air treated by the air treatment unit with a second virucidal photoreactor filter (5) before the air is introduced into the ducting (2), finally it provides that at each diffuser (3), the air must pass through an additional virucidal photoreactor filter (6).

[0033] Fig. 7 shows a schematic view of a virucidal photoreactor filter, comprising a three- dimensional lattice (7) irradiated by a series of ultraviolet lamps (8) that activate the bactericidal and virucidal reaction through photocatalysis. The entire filter is enclosed in a casing (9) that prevents the escape of ultraviolet radiations.

[0038]

[0034] Fig. 8 shows a schematic view of a virucidal photoreactor filter, comprising a three- dimensional lattice (7) irradiated by two series of lamps (8) that activate the bactericidal and virucidal reaction through photocatalysis. The entire filter is enclosed in a casing (9).

[0039]

[0035] Fig. 9 schematically shows the presence within the filter of a plurality of filtering channels oriented so as to reduce pressure drops and, at the same time, increase the filtering surface.

[0040]

[0036] Fig. 10 schematically shows that the three-dimensionality of the filtering channels is also achieved on the filter's surface.

[0041] Detailed description of an embodiment of the invention

[0042]

[0037] The detailed description that follows, concerning an embodiment of the invention, provided purely as a non-limiting example, with reference to the attached drawings, highlights the further features and advantages deriving from the present invention, which are an integral part thereof.

[0043]

[0038] In a preferred embodiment of the invention, the filtering apparatus that accommodates it comprises at least one air treatment unit (1), aeraulically connected to one or more diffusers (3) via a suitably branched ducting (2), within which at least one virucidal photoreactor filter (11) is placed. For ease of implementation, the photoreactor filtering device can be located at the inlet opening of the treatment unit, however, other embodiments are possible, such as the one shown in Fig. 6, where a virucidal photoreactor filtering device (4) is placed at the air inlet opening and a second virucidal photoreactor filtering device (5) at the treated air outlet opening. Further virucidal photoreactor devices (6) are located at the outlet openings of the diffusers (3).

[0044]

[0039] In a particularly comprehensive embodiment, the filtering device comprises at least one three-dimensional virucidal filter (11), with its internal surfaces at least partially coated with photoreactive material, such as Titanium Dioxide and Silver, and irradiated with ultraviolet light emitted by a plurality of UV-C LEDs; these LEDs are controlled by an electronic control unit (12), which regulates their light emission and is connected to a plurality of sensors, whose signals are processed by the electronic control unit to diagnose the filter's actual efficiency and maintenance status. Furthermore, the electronic control unit is connected externally, either via cable or radio, so as to communicate the information it collects and stores in a log file to the maintenance service.

[0045]

[0040] The filters of the virucidal photoreactor devices are made of polyester, preferably using molding and / or weaving technology, and include a three-dimensional lattice coated with a thin layer of photoreactive material, this latter preferably including Titanium Dioxide. In a particularly effective embodiment, said thin layer of photoreactive material can also include Silver.

[0046]

[0041] The aforementioned three-dimensional lattice is irradiated by LED lamps that preferably emit UV-C ultraviolet light in the range between 200 and 380 nm, thereby achieving a significant virucidal and / or bactericidal effect.

[0047]

[0042] To assess the actual degree of filter clogging, the filtering device of the present invention includes an anemometer for detecting the fluid dynamic pressure drop imposed by the filter on the gaseous flow passing through it. In more complete and high-performance versions, there is also at least one limiter of electrical power supply surges and at least one sensor for detecting the intensity of the UV-C LEDs, in order to verify their effectiveness and thus the proper sanitization of the filter; with this sensor, it's also possible to determine if there are any faulty LEDs in the filtering device that need to be promptly replaced to ensure the continuation of the virucidal action.

[0043] According to a particularly effective embodiment, the filtering device includes devices for measuring the pressure at the inlet and outlet of said three-dimensional virucidal filter.

[0048]

[0044] Advantageously, the invention can also include at least one thermal sensor to verify the actual operating temperature.

[0049]

[0045] The filtering device of the present patent comprises a peripheral frame (14) which, very advantageously, can have the same dimensions as the filtering devices already installed on existing vehicles, so that it can be easily installed on all rolling stock already in operation; said peripheral frame can be made of hypoallergenic material.

Claims

CLAIMS1. A dynamic filtering device for aeraulic apparatuses of passenger transport vehicles characterized in that it comprises:- at least one three-dimensional filter (11), with surfaces at least partially coated with photoreactive material, such as Titanium Dioxide and Silver and irradiated by UV-C LEDs;- at least one anemometric device for detecting the fluid dynamic pressure drop imposed by the filter on the air flow passing through it;- at least one sensor for detecting the intensity of the UV-C LEDs to verify their effectiveness and therefore the correct sanitization of the filter;- at least one electronic control unit (12) for processing the diagnostic parameters and for powering and controlling the radiation emitted by the UV-C LEDs, varying their emissions according to the actual air flow; said control unit being telematically interfaceable with the maintenance equipment, both on board the vehicle and in the workshop.

2. Filtering device as per claim 1 above, characterized in that it comprises at least one limiter of electrical power supply surges.

3. Filtering device according to one of the preceding claims, characterized in that it comprises devices for measuring the pressure at the inlet and outlet of said filtering devices.

4. Filtering device as per one of the preceding claims, characterized in that it comprises means of radio communication (13) to interface said control unit (12) with said maintenance equipment.

5. Filtering device as per one of the preceding claims, characterized in that it comprises at least one thermal sensor for detecting the actual operating temperature interfaced with said electronic control unit (12).

6. Filtering device as per one of the preceding claims, characterized in that said at least one three-dimensional filter (11) comprises a peripheral frame (14) having the same dimensions as the filters already installed on existing vehicles.

7. Filtering according to the preceding claim, characterized in that said perimeter frame (14) is made of hypoallergenic material.

8. Filtration apparatus for a ventilation system, especially suitable for the treatment andexchange of air in vehicles used for the transport of people, comprising at least one air treatment unit (1), a branched ducting (2) which delivers the air exiting said treatment unit to one or more diffusers (3) characterised in that along its path the air passes through at least one filtering device as per preceding claims 1 to 7.

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