Disinfecting method and control unit thereof

Abstract

Method for washing and / or drying objects that includes at least one washing and / or drying step (Fl) and a disinfecting step (F2) by means of an emitter unit (23) comprising a set of three primary emitters (26A, 26B, 26C) and a secondary emitter (27).

Description

[0001] DISINFECTING METHOD AND CONTROL UNIT THEREOF

[0002] FIELD OF THE INVENTION

[0003] This invention relates to a method that uses the disinfecting function during, before or after the washing and / or drying cycle of a washing and / or drying machine used in a domestic or professional setting, such as a dishwasher, washing machine, tumble dryer or other similar or analogous machine. The disinfecting method according to the present invention that, as will be explained in greater detail below, makes it possible to reduce and / or inhibit the action of one or more microorganisms such as, for example, bacteria, viruses, fungi, spores, or moulds, within an operating chamber of the machine itself, whether it is the dishwashing chamber, or the basket for washing and / or drying cloths.

[0004] Although the present description will mainly concern washing machines or similar, the present invention as described herein can also be applied in other contexts, for example furnishing elements in general, domestic or shared use environments such as offices, shops, schools, gyms, etc.

[0005] STATE OF THE ART

[0006] Machines for washing and / or drying dishes, cloths or other objects are known, which typically define an operating chamber in which the washing and / or drying of such objects takes place by means of liquid or gaseous fluids, at different temperatures, to carry out predefined, or predefinable, operating cycles, according to predefined washing and / or drying methods, for example managed electronically by relevant control units.

[0007] It is also known that, precisely for the cleaning action or, in any case, for the washing and / or drying treatment that these known machines carry out, different types of microorganisms such as bacteria, viruses, fungi, spores, or moulds can be generated or developed, even on several occasions, within their operating chambers. The presence of these microorganisms within the operating chamber partially compromises the treatment carried out by the known machine, especially with regard to the degree of final hygiene of the objects being washed and / or dried.

[0008] Currently, the removal of microbial loads inside the operating chambers of known machines takes place through operating methods which provide for systematic cleaning cycles, using, for example, chemical additives and starting predefined washing cycles.

[0009] This solution, although dependent on the user's consistency in carrying it out, does not always guarantee sufficient and effective removal of microorganisms. In addition, chemical additives can be particularly aggressive to the internal components of the machine, in particular with regard to plastic components or metal coatings, which, with repeated cleaning cycles, can be damaged to the point that they lose their original functionality, necessitating extraordinary maintenance, or replacement, at the user's expense.

[0010] Machines are also known that have lighting devices configured to light up when opened to inspect the interior, and these are typically oriented to illuminate the dishes directly.

[0011] Washing and / or drying machines are also known which, in order to keep energy consumption and electronic operating costs low, are provided with UV-C ray diffusers inside them. However, UV-C rays, by their nature, do not guarantee the elimination of microorganisms, but only carry out an action of temporary inactivation of the same, meaning that the pathogens resume their vitality after a certain period of time, which means that effective disinfecting of the environments and surfaces is not guaranteed.

[0012] UV-C also has the additional defect that it is often absorbed by water vapour and therefore cannot effectively illuminate the compartment. This is also the case on the walls because they absorb part of the electromagnetic radiation.

[0013] Furthermore, these and other types of known devices, for example not necessarily using UV-C ray diffusers, have been found to be particularly aggressive on the materials of the machine components and of the objects treated in the washing / drying, for example by interacting and deteriorating polymers and rubbery materials and by discolouring some fabric colours and / or the materials themselves.

[0014] In addition, the known devices, to emit the desired radiation for both light and disinfecting, work at voltages of approx. 22-36 V, requiring customized power supplies, or drivers, therefore with increased costs and higher energy consumption.

[0015] Furthermore, when using certain solutions with more advanced LED emitters, lighting devices currently need to be operated by the user from the outside, meaning that the effectiveness of disinfecting operations is heavily dependent on both the user's skill in operating these devices and, in any case, the consistency and frequency of use, according to the user's preferences. This external manual action carried out by the user does not guarantee a qualitative repeatability of the disinfecting treatment carried out.

[0016] From KR 102 659 836 a disinfecting method is known in a machine comprising a washing chamber in which there are two single-frequency emitters for emitting an optical signal in the range 380-420 rnn.

[0017] These single-frequency emitters do not obtain a significant disinfecting effect, as they do not effectively and specifically neutralise the bacteria that are most harmful to human health.

[0018] There is therefore the need to perfect a disinfecting method that can overcome at least one of the disadvantages of the state of the art.

[0019] It is also known that there is a need to devise a disinfecting method for a washing and / or drying machine, which can obtain uniform and homogeneous diffusion of electromagnetic radiation, for protection against microbiological contamination, at least within the operating chamber and throughout its entire volume.

[0020] It is also known the need to devise a disinfecting method that allows effective disinfection to be achieved quickly with low energy consumption.

[0021] To do this, it is necessary to solve the technical problem of disinfecting the operating chamber of a washing and / or drying machine without the need for external manual intervention and without requiring special expertise and individual skills.

[0022] In particular, one purpose of the present invention is to devise a disinfecting method that makes it possible to perform an effective disinfection of at least one operating chamber of the washing and / or drying machine to which it is applied, in an optimized, uniform and repeatable way, with energy consumption and low costs.

[0023] Another purpose of the invention is to devise a disinfecting method that provides highly effective disinfection in eliminating microorganisms that are sensitive to electromagnetic radiation.

[0024] The Applicant has devised, tested and embodied the present invention to overcome the shortcomings of the state of the art and to obtain these and other purposes and advantages. SUMMARY OF THE INVENTION

[0025] The present invention is set forth and characterized in the independent claims. The dependent claims describe other characteristics of the present invention or variants to the main inventive idea.

[0026] In accordance with the above purposes and to resolve the above technical problems in a new and original way, also achieving considerable advantages compared to the state of the prior art, a disinfecting method according to the present invention is applied to machines for washing and / or drying objects, such as for example dishes, cloths or others, in a domestic or professional operating context.

[0027] The method according to the present invention generally comprises at least one washing and / or drying step performed in operating chamber substantially defined by a containing structure, by a front and / or upper aperture, from which the objects are loaded, and by at least one bottom wall, opposite to the front aperture or to the upper one with respect to the containing structure.

[0028] Advantageously, the front / upper aperture can be associated with a door, a porthole or in any case a movable element that defines the watertight closure of the operating chamber.

[0029] In embodiments, wherein the machine to which the disinfecting method applies according to the present invention is intended for washing and / or drying dishes, the containing structure is substantially defined by at least two side walls, a lower wall and an upper wall, all connected to each other and to the lower wall, to define a substantially parallelepiped or cubiform operating chamber.

[0030] In other embodiments, wherein the machine to which the disinfecting method applies according to the present invention is intended for washing and / or drying clothes, the containing structure is substantially defined by a rotating basket and at least one circular gasket, interposed between the rotating basket and the front aperture, to define a substantially cylindrical operating chamber.

[0031] In accordance with one aspect of the present invention, the method comprises at least one disinfecting step, in which at least one emitter unit is activated, cooperating with the operating chamber, which in turn comprises a set of three primary emitters and at least one secondary emitter. At least one emitter unit can be housed in a housing seating.

[0032] Each set of three comprises three primary emitters that are different from each other, each configured to emit electromagnetic radiation having a wavelength with a specific peak value different from the other two primary emitters.

[0033] Preferably, the primary emitters are adapted to emit a light radiation in the violet spectrum, indicatively comprised between 380 nm and 435 nm and the at least one secondary emitter is adapted to emit a light radiation in the blue spectrum, indicatively comprised between 435 nm and 500 nm.

[0034] According to one aspect of the invention, the set of three primary emitters comprises:

[0035] - a first emitter configured to emit an electromagnetic radiation having a peak value with wavelength comprised between 404 nm and 409 nm, advantageously 407 nm;

[0036] - a second emitter configured to emit an electromagnetic radiation having a peak value with wavelength comprised between 411 nm and 416 nm, advantageously 413 nm;

[0037] - a third emitter configured to emit an electromagnetic radiation having a peak value with wavelength comprised between 418 nm and 424 nm, advantageously 420 nm.

[0038] The at least one secondary emitter is configured to emit an electromagnetic radiation having a peak value with wavelength comprised between 452 nm and 458 nm, with a preferential peak value of 455 nm.

[0039] This combination of primary emitters with different wavelengths, together with the secondary emitter, for example in a 1: 1: 1: 1 ratio, allows to obtain a total substantially uniform electromagnetic radiation flux with peak values between 400 nm and 470 nm and preferably between 402 nm and 460 nm, even more preferably centred in the range from 404 nm to 424 nm and between 450 nm and 460 nm.

[0040] Therefore, the solution according to the present invention provides a method that allows to perform internal disinfection of the operating chamber of a washing and / or drying machine, according to pre-ordered and / or programmable cycles, that is, without the need for the intervention of an external operator, particularly to remove microorganisms including Gram+, Gram-, viruses, spores, moulds, fungi, mites and yeasts that are potentially harmful to humans.

[0041] In particular, the overlapping of the irradiated cones emitted by the individual primary emitters with different wavelengths means that the overall cone emitted by the emitter unit, defined by the interference and combination of the individual cones emitted by the four emitters or their respective multiples, is already focused and centred on wavelengths with a high antimicrobial and bactericidal effect.

[0042] Using a multi-peak light spectrum, i.e. simultaneously emitting multiple selected wavelengths in the visible light region, exploits the principle of spectral resonance, which describes the ability of particular light frequencies to effectively interact with specific biological targets in bacteria.

[0043] These targets, which include molecules such as porphyrins, flavins, NADH and cytochromes, and sub-cellular structures such as membranes and DNA, react selectively at certain light frequencies, generating harmful biological effects for bacteria.

[0044] Compared to a mono-peak spectrum, which is focused on a single light frequency and thus limits the number of molecular structures involved, the multipeak spectrum obtained in the present invention makes it possible to interact simultaneously with a greater number of biological targets. This approach expands the biological coverage, thus maximizing the antibacterial effect through a more complete and targeted resonance.

[0045] The simultaneous use of multiple frequencies allows synergistic effects to be generated, simultaneously causing oxidative stress, direct structural damage to bacterial membranes, genetic alterations and enzyme inhibitions. The multiplicity of frequencies also makes it harder for bacteria to develop resistance mechanisms, because adapting to multiple simultaneous stimuli is complex and biologically less likely.

[0046] The use of emitters as described above exploits in particular the photodynamic action of the frequencies used, specifically promoting light absorption by bacterial chromophores. This combined mechanism is extremely effective at amplifying the overall bacterial damage.

[0047] The emitter according to the present invention implements this multi-frequency approach using three distinct spectral bands, which advantageously and respectively have their own peaks at 407 nm, 413 nm and 420 nm, in the region of visible light. These specific peaks are selected for their ability to enter biological resonance, that is, to selectively stimulate target molecules typical of bacteria such as porphyrins, flavins and other chromophore proteins. Biological resonance refers to the phenomenon whereby a specific light frequency interacts specifically with a biological molecule, inducing an effective and targeted response that amplifies the antibacterial effect due to a precise and intensified action on sensitive cellular structures.

[0048] This configuration allows continuous disinfection in inhabited environments without damage or risk to human and animal health.

[0049] The adoption of the multi-peak spectrum according to the present invention represents a considerable innovation with respect to the single-frequency light sources used in the prior art. This approach ensures enhanced antibacterial efficacy, high operational safety, and a significant reduction in the ability of bacteria to develop resistance.

[0050] It should also be noted that the emitter of the present invention, characterized by wavelengths between 400 and 460 nm, is particularly effective for use in controlling pest insects. In fact, it has been shown that blue wavelengths, especially around 420 nm, represent an alternative instrument to traditional chemical methods.

[0051] Irradiation with blue light at 417 nm has been shown to have a significant lethal effect on mosquito larvae and pupae.

[0052] Irradiation with blue light in a range of wavelengths between 404 and 467 nm is lethal for different vital stages of insects. In particular, the very marked lethal action around 417 nm is very effective on mosquitoes, with a sharp increase in the mortality of pupae, confirming the species-specificity of these wavelengths in counteracting insects.

[0053] The lethal effect of blue light appears to be primarily associated with the production of reactive oxygen species (ROS), which severely damage insect tissues. This mechanism of action, which exploits the formation of ROS resulting from the absorption of light by specific chromophores in insect tissues, is safe for the environment and free of toxic residues compared to traditional chemical insecticides.

[0054] Therefore, the light spectrum obtained with this invention, with wavelengths between 400 and 460 nm, is an effective, environmentally sustainable and promising technical solution for controlling insect populations.

[0055] According to embodiments, emitter units are provided in which there are N first emitters, N second emitters, N third emitters and N secondary emitters, such that the 1 : 1 : 1 : 1 ratio is maintained and repeated each time.

[0056] In another embodiment, there are 2, 3, 4, 5 or more secondary emitters for each set of three of primary emitters.

[0057] The solution according to the present invention therefore has the advantage of allowing the execution of an effective disinfecting at least of the operating chamber, in an optimized and repeatable way, with low energy consumption and low costs.

[0058] In fact, considering a voltage of approx. 3 V, for each of the primary emitters and the secondary emitter, each emitter unit requires a voltage of approx. 12V, or multiples thereof, that is, a voltage that is likely to be manageable with standardized power supplies, or drivers, therefore with low costs and reduced energy consumption.

[0059] In the 12V powered version, the LEDs can have a power supply scheme that includes 4 LEDs powered in series, or two series powered in parallel to each other, of 4 LEDs.

[0060] This power supply configuration advantageously allows the balancing of currents on the internal branches, allowing the use within the acceptance ranges of the individual internal chips.

[0061] A variant provides for the recalibration of the chemical composition of an additional phosphor layer in order to maintain the colourimetric coordinates, and consequently the colour temperatures, within the acceptance range for professional lighting according to ANSI C78.377

[0062] The spectral emission and its efficiency with respect to white emission is slightly lower than a 24 volt version, but the energy transmitted in the range of wavelengths ranging from 400 to 420 nm is increased by approx. 25%.

[0063] As mentioned above, the use of a 36V power supply falls within the scope of the present invention, with the consequent possible modification of the configuration of the connections between the LEDs and variation of the position of the chips to promote the uniformity of light emission compared to the 12V or 24V configuration, while maintaining the logic of distances and alternation between adjacent wavelengths.

[0064] This functional advantage allows a perfect integration of the at least one emitter unit in a traditional washing and / or drying machine, guaranteeing an additional power absorption, however, of less than 15W.

[0065] In other words, the emitter unit according to the present invention, being designed to operate at 12V or its multiples, makes it possible to extend the possible combinations that can be used while maintaining low consumption, even in the order of approx. 4W. In the specific application, the powers in play have been modified so that the disinfecting system can be inserted into the control electronics of the washing and / or drying machine, falling into low consumption energy bands.

[0066] With the method according to the present invention it is possible to provide the possibility of performing highly effective disinfecting by destroying microorganisms sensitive to electromagnetic radiation.

[0067] In accordance with another aspect of the present invention, the disinfecting step is initiated with timing offset with respect to the washing and / or drying step. According to a variant, the disinfecting step is started with simultaneous timing with respect to the washing and / or drying step.

[0068] In accordance with another aspect of the present invention, the disinfecting step has a duration comprised between about 120 minutes and about 360 minutes. However, solutions in which the disinfecting step lasts between about 100 minutes and about 360 minutes are not excluded.

[0069] In accordance with another aspect of the present invention, the disinfecting step is started immediately upstream of the washing step, i.e. immediately downstream of the washing step.

[0070] In accordance with another aspect of the present invention, a control unit is provided, which is electronically connected at least to the emitter unit, and configured to control the selective activation thereof, according to a predefined programming, or is selectively definable.

[0071] In accordance with another aspect of the present invention, the emitter unit comprises at least one electronic support configured to support the set of three of primary emitters and the at least one secondary emitter, and at least one support element, which is arranged in direct cooperation with the housing seating, and is configured to support and maintain the electronic board, in a certain position, in which the set of three of primary emitters and the at least one secondary emitter, emit the light radiation inside the operating chamber.

[0072] Here and in the following, by way of example and not for this limiting, the electronic board may be a support package for emitters, for example LEDs. Advantageously, the electronic board can be a package of the type SMD, COB, DOB, Flip LED or other similar packages.

[0073] In accordance with another aspect of the present invention, the emitter unit comprises at least one refraction element, arranged in direct cooperation with the housing seating, and configured to cooperate with the set of three primary emitters and the at least one secondary emitter, so as to condition the refraction of the light radiation emitted inside the operating chamber, on a refraction plane defining a specific refraction angle, with respect to an emission plane, the latter being substantially orthogonal to the containing structure.

[0074] In this advantageous embodiment of the present invention, the reflective capacity of the internal surfaces of the operating chamber is exploited to diffuse the electromagnetic emission within the operating chamber itself in a substantially uniform maimer, also bypassing the functional equipment of the machine, for example the racks in the dishwashers, so as to guarantee complete disinfecting of the operating chamber.

[0075] The LEDs used in the present invention are designed to emit electromagnetic radiation in the violet and blue spectrum, with wavelengths between 400 nm and 420 nm. This choice of wavelengths offers some significant advantages over the use of UV-C rays or other disinfecting technologies.

[0076] For example, the wavelengths produced by the emitters present in the LEDs according to the present invention (380-500 nm) interact with water differently than the UV-C rays traditionally used (200-280 nm), where the interaction of light with water is mainly influenced by refraction, absorption and dispersion phenomena, better known as scattering.

[0077] In fact, the index of refraction of water varies with the wavelength of light due to a phenomenon known as optical dispersion, decreasing as the wavelength increases. For UV-C wavelengths between 200 nm and 250 nm this ranges from 14.98 • 10'1to 13.96 • 10’1, while for wavelengths in the portion of the visible spectrum between 380 nm and 500 nm, as from the solution according to the present invention, this ranges from 13.43 • 10'1to 13.33 • 10'1. This difference reduces the angle of refraction for the wavelengths of the LEDs according to the present invention, minimizing the dispersion of light. In addition, water has an absorption coefficient for UV-C rays between 200 and 250nm of approx. 104-103cm-1, while for the violet and blue wavelengths the absorption coefficient falls to values between approx. 0.01 cm1and 0.001 cm'1. This means that the wavelengths emitted by the LEDs according to the present invention are absorbed much less by water than traditional solutions, allowing a deeper penetration.

[0078] With the solution according to the present invention, the water and the walls do not have absorption effects but rather effectively reflect light so as to homogeneously illuminate the compartment. In addition, these UV-C lights are also somewhat energy-intensive and need dedicated power supply systems. In the present invention, the necessary power supply can be taken directly from the control unit.

[0079] Finally, the phenomenon of scattering is also a key factor that influences the effectiveness of electromagnetic radiation in the penetration of water droplets. With regard to the scattering phenomenon, a distinction is made between Rayleigh scattering and Mie scattering.

[0080] With regard to Rayleigh scattering for water, a proportional coefficient of-4is expected, while for UV-C rays the scattering coefficient is significantly higher than for violet and blue wavelengths. This means, that applying the known formulas, the scattering coefficient for wavelengths at 250 nm is approx. 9.73 X 1022m-1, while for wavelengths at 400 nm it is approx. 1.48 X 1022m-1.

[0081] With regard to Mie scattering, there is a substantially less wavelength-dependent condition than Rayleigh scattering, but, in any case, the shorter wavelengths (UV- C rays) suffer a greater scattering effect.

[0082] Thus, since the wavelengths of the LEDs according to the present invention are less susceptible to both the effects of refraction and absorption, and the effects of Rayleigh scattering and Mie scattering with respect to UV-C rays, the visible electromagnetic radiation can be more uniformly distributed within the operating chamber.

[0083] This advantageous aspect of the solution according to the present invention ensures that all surfaces and objects inside the chamber receive an adequate dose of disinfecting radiation.

[0084] DESCRIPTION OF THE DRAWINGS These and other aspects, characteristics and advantages of the present invention will become apparent from the following description of some embodiments, given as a non-restrictive example with reference to the attached drawings wherein:

[0085] - fig. 1 is a schematic and partially sectioned view of a first embodiment of a washing and / or drying machine, to which the disinfecting method applies according to the present invention;

[0086] - fig. 2 is a schematic view of a second embodiment of a washing and / or drying machine according to the present invention;

[0087] - fig. 3 shows an enlarged detail of fig. 1;

[0088] - fig. 4 shows a section along the line IV-IV of fig. 3;

[0089] - fig. 5 is a schematic view of an emission unit in accordance with a first variant of the invention, in which the different emitters are indicated by respective letters

[0090] - fig. 6 is a graph showing the emission spectrum of the individual primary emitters and the spectrum resulting from their combination;

[0091] - fig. 7 schematically illustrates a flow-chart of a first form of operating sequence of the method according to the present invention;

[0092] - fig. 8 schematically illustrates a flow-chart of a second form of operating sequence of the method according to the present invention; and

[0093] - fig. 9 schematically illustrates a flow-chart of a third form of operating sequence of the method according to the present invention.

[0094] We must clarify that in the present description the phraseology and terminology used, as well as the figures in the attached drawings also as described, have the sole function of better illustrating and explaining the present invention, their function being to provide a non-limiting example of the invention itself, since the scope of protection is defined by the claims.

[0095] To facilitate comprehension, the same reference numbers have been used, where possible, to identify identical common elements in the drawings. It is understood that elements and characteristics of one embodiment can be conveniently combined or incorporated into other embodiments without further clarifications.

[0096] DESCRIPTION OF SOME EMBODIMENTS OF THE PRESENT INVENTION

[0097] With reference to figures 1 and 2, two different embodiments of a washing and / or drying machine 10 are illustrated, to which a disinfecting method according to the present invention is applied, both provided with an operating chamber 11 defined by a containing structure 12, by a front aperture 13 and by at least one bottom wall 14.

[0098] The machine 10 should be considered as only representative of other types of washing / drying machines, for example with upper apertures, with multiple and separate washing chambers, of any shape and size.

[0099] Furthermore, although the description refers mainly to washing and / or drying machines mainly of the domestic type, the invention can also be applied in washing / drying machines of the industrial type and of much larger or even smaller dimensions than machines for predominantly domestic use.

[0100] A control unit 50 is electronically associated with the machine 10, only schematized in the accompanying figures, which is programmed, or selectively programmable, to define a desired operating sequence of the operating steps of the method according to the present invention, as will be explained in detail below.

[0101] In particular, the schematized and partially sectioned machine 10 of fig. 1 is configured in a dishwasher, whether domestic or professional, in which the lateral containing structure 12 is defined by two side walls 15, a lower wall 16, and a top wall 17, connected to each other and to the bottom wall 14, so as to give the operating chamber 11, which in this solution can be called a washing chamber, a substantially parallelepiped conformation.

[0102] Typically, the front aperture 13 is selectively reclosable by means of a door 18, hinged to the lower wall 16, so as to define the watertight closure of the operating chamber 11, allowing the operations to start the operating cycle.

[0103] In the embodiment illustrated in fig. 2, the machine 10 is intended to represent a washing machine, i.e. a dryer, whether of the domestic or professional type, in which the containing structure 12 is defined by a rotating basket 19 and at least one circular gasket 20, interposed between the rotating basket 19 and the front aperture 13.

[0104] Typically, the front aperture 13 can be selectively closed by means of a door 21, so as to define the watertight closure of the operating chamber 11, allowing the operations to start the operating cycle.

[0105] Both in the solution of the dishwasher schematized in fig. 1, and in the solution of the washer / dryer shown in fig. 2, the machine 10 can comprise at least one housing seating 22 in which the electromagnetic radiation emitter unit 23 can be positioned, in a suitable maimer and with suitable orientation.

[0106] Advantageously, in the solution illustrated in figures 1, 3 and 4 there are eight housing seatings 22, of which only four are represented, and obtained on relative niches 24, the latter defined by structural stiffening bosses of the side walls 15 normally present in this type of machine. This solution makes it possible to maintain the normal structural designs of traditional dishwashers, without requiring specific modifications to the production moulds, or any of its components.

[0107] Advantageously, in the solution illustrated in figure 2, the housing seating 22 is obtained in the upper part of a typical groove 25 of the circular gasket 20. Here too, taking advantage of the parts already present in the traditional washer / dryer, it is possible to maintain the normal designs, without requiring specific modifications of the production moulds, or its components.

[0108] Common to the two solutions, each emitter unit 23 comprises a support, or electronic board 28, configured to support a set of three of primary emitters 26A, 26B and 26C, and at least one secondary emitter 27, of the same emitter unit 23. Advantageously, the electronic board 28, or at least the portion thereof on which the emitters 26A, 26B, 26C and 27 are installed, has a substantially rectangular shape, so as to allow the emission of a total light beam within a well-defined cone.

[0109] According to the embodiment in fig. 5 the emitter unit 23 provides for a single group of primary emitters 26A, 26B and 26C, and a secondary emitter 27, while in other embodiments not represented in the accompanying figures, 3, 6, i.e. 12, groups of primary emitter units 26A, 26B and 26C, and a secondary emitter 27, can be provided in the same emitter unit 23.

[0110] As a general scheme, each emitter unit 23 may comprise four emitters among the three primary emitters 26A, 26B, 26C, and the secondary emitter 27, in a ratio of 1 : 1 : 1 : 1, and in any case providing for the possibility that there may be N primary emitters 26A, N second emitters 26B, N third emitters 26C, and N secondary emitters 27, such that the ratio 26A:26B:26C:27 = 1: 1: 1: 1 is always maintained.

[0111] In each case, each emitter unit 23 further comprises a refraction element, or lens 29, arranged facing inside the operating chamber 11 and in direct cooperation with the housing seating 22, and a supporting element, or capsule 30, arranged in direct cooperation with the housing seating 22, on the opposite side to the lens 29 and configured to maintain the electronic board 28, in a certain position of emission of the light radiation, towards the inside of the operating chamber 11.

[0112] Advantageously, the lens 29 and the capsule 30 cooperate elastically with each other, by means of relative snap-fit members 31, which also define a stable clamping of the side wall 15 between the lens 29 and the capsule 30.

[0113] Advantageously, on the inside of the operating chamber 11, i.e. in cooperation with the lens 29, at least one gasket is provided, for example an o-ring, so as to make the mounting of each emission group 23 in the relative housing seating 22 watertight.

[0114] In particular, the lens 29 has a shaped portion 33, which faces inside the operating chamber 11, and provides a surface pattern such that it asymmetrically conditions the refraction of the light radiation emitted by the set of three primary emitters 26 A, 26B and 26C, and the secondary emitter 27. In the solution shown in fig. 4, the asymmetric conditioning of the light radiation takes place on a refraction plane Pl defining a certain refraction angle a, with respect to an emission plane P2, the latter substantially orthogonal to the side wall 15 on which the housing seating 22 is obtained. Advantageously, the refraction angle a can be between approx. 50° and approx. 70°.

[0115] Furthermore, as schematized in fig. 3, the shaped portion 33 is configured so as to expand the refraction of the emitted light radiation with a certain expansion angle fl, the latter lying on the refraction plane Pl.

[0116] A compact and homogeneous beam of light radiation is thus defined which, according to the orientation given to the shaped portion 33, is directed towards the bottom wall 14, or towards another suitable wall suitably selected on the basis of the specific geometry, such as for example the door 18.

[0117] In other embodiments, part of the emission units 23 provided can affect the rear wall 14, while others the door 18, but also the upper walls 17 or lower walls 16, depending on convenience, the specific geometry and the internal structures of the machine, with a certain angle of incidence [3 (fig. 4), and from here the radiation can be reflected uniformly inside the operating chamber 11. Advantageously, the angle of incidence [3 may be between approx. 20° and approx. 40°. According to some variants not illustrated in the attached figures, in combination or in place of the oriented lens 29 the radiation can also be directed by appropriately shaping the housing seating 22.

[0118] With regard to the set of three primary emitters 26A, 26B and 26C, and to the secondary emitter 27, the solution according to the present invention provides that the set of three of primary emitters 26A, 26B and 26C comprises:

[0119] - a first emitter 26A configured to emit an electromagnetic radiation having a peak value with wavelength XI comprised between 404 nm and 409 nm, with a preferential peak value of 407 nm;

[0120] - a second emitter 26B configured to emit an electromagnetic radiation having a peak value with wavelength X2 comprised between 411 nm and 416 nm, with a preferential peak value of 413 nm; and

[0121] - a third emitter 27C configured to emit an electromagnetic radiation having a peak value with wavelength X3 comprised between 418 nm and 424 nm, with a preferential peak value of 420 nm.

[0122] The secondary emitter 27 is configured to emit an electromagnetic radiation having a peak value with wavelength X4 comprised between 452 nm and 458 nm, with a preferential peak value of 455 nm.

[0123] Other components, not illustrated, such as for example one or more temperature sensing sensors, power supply, conversion systems, microcontrollers or the like may also be provided on the electronic board 28.

[0124] According to some variants, the primary emitters 26A, 26B and 26C and the secondary emitter 27, may provide a platelet, not illustrated and known as chip or DIE, which is made of semiconductor material and configured to emit a substantially mono-frequency highly focused radiation with the desired wavelength. For example, this may be achieved by doping the semiconductor material.

[0125] Preferably, both the primary emitters 26A, 26B, 26C and the secondary emitter 27 are configured to emit a radiation within a very narrow and precise range of the wavelength, for example of about 4-8 nm centred on the respective peak value. Preferably, the range of the wavelength around the respective peak value is ± 3nm.

[0126] From a comparative analysis of a single LED emission at a certain wavelength, for example 405 nanometres, it can be seen how the FWHM value changes significantly with respect to the emission of two or more neighbouring wavelengths emitted at the same time.

[0127] FWHM (Full Width at Half Maximum) refers to the width of the spectral curve of the LED measured at half the maximum height of the light emission. In practice, this means how narrow or wide the band of light emitted by the LED is at a certain wavelength.

[0128] The meaning of FWHM is as follows:

[0129] Narrow FWHM: Means that the LED emits a light with a very narrow wavelength range, i.e. a very "pure" light from a spectral point of view (selective or narrow spectral emission).

[0130] Wide FWHM: Means that the LED emits a light with a wider wavelength range, i.e. a less "pure" light from a spectral point of view, but richer and more uniform at the energy level in the wavelength bands of interest (wide or less selective spectral emission).

[0131] This parameter is normally used to define the purity and spectral quality of the colour emitted by a single frequency, but can be used in this case to better understand how the approach of a multifrequency as in the present invention can favour the disinfecting effect with respect to a single wavelength with the same emission intensity.

[0132] In the context of interaction with gram-positive and gram-negative pathogens, FWHM takes on particular relevance because bacteria possess different chromophores (light-sensitive molecules such as porphyrins, flavins, NADH, and cytochromes) characterized by specific absorbance spectra. These spectra determine which wavelengths the bacteria respond to most, enabling targeted disinfection via spectral resonance.

[0133] Take for example the mapped spectral emission of a 405 nanometre source with a peak intensity of 0.332 W / nm @ 405nm

[0134]

[0135] Applying the calculation to derive the FWHM value in nanometres, the spectral width is approximately 10 nanometres, as would be expected from a classic 5 monochromatic source. This determines the ability to transfer an average level of energy in the Soret band to the bacterial species to be treated within a limited spectral width, which also explains very well why single frequencies require very high intensities or very long exposures in order to achieve satisfactory treatments. This feature, a narrow FWHM, ensures high precision, but significantly limits the number of biological molecules that can be stimulated simultaneously.

[0136] The biological interaction is thus limited to a narrow group of chromophores (e.g., predominantly porphyrins), with reduced biological coverage and potentially lower energy efficiency than the diversity of existing bacteria. The multifrequency approach, on the other hand, is characterized by the use of three monochromatic LEDs that emit at close but distinct wavelengths in order to cover the entire Soret band with a constant average energy level. Below is an example of the emission of the single constituent LED according to the present invention:

[0137] The energy emission of each individual LED is calibrated in order to have a uniformly distributed source resulting from the sum of the emission at the individual three wavelengths with a peak between 413 and 414 nanometres.

[0138]

[0139] This makes it possible to have a resultant emission that covers a very wide band of wavelengths with a high average energy.

[0140] The FWHM value in the emitter according to the present invention is approx.

[0141] 20 nm, twice that of a monochromatic source, considering the same peak energy emission value.

[0142] Due to this higher spectral amplitude, the average light energy transmitted to pathogens is significantly higher, because it covers a wider range within the absorbance spectra of bacteria, thus increasing the probability of interaction with multiple biological targets simultaneously.

[0143] The technology according to the present invention uses a multi-peak light spectrum, i.e. it simultaneously emits several selected wavelengths in the region of visible light. This choice is linked both to the greater energy efficiency with respect to the treated bacterial species, affecting a wider spectrum of absorbance, and to the principle of spectral resonance, which describes the ability of particular light frequencies to interact effectively with specific biological targets in bacteria. These targets, which include molecules such as porphyrins, flavins, NADH and cytochromes, and sub-cellular structures such as membranes and DNA, react selectively at certain light frequencies, generating harmful biological effects for bacteria.

[0144] Compared to a mono-peak spectrum, which is focused on a single light frequency and thus limits the number of molecular structures involved, the multipeak spectrum of the present invention makes it possible to interact simultaneously with a greater number of biological targets. This approach expands the biological coverage, thus maximizing the antibacterial effect through a more complete and targeted resonance.

[0145] The substantial difference in FWHM between the two approaches (10 nm for single frequency vs. 20 nm for the multifrequency of the present invention) is not just a technical issue, but reflects a different biological approach: the emitter according to the present invention amplifies and diversifies biological interaction, achieving higher levels of average energy transferred to pathogens and simultaneously generating a plurality of harmful effects on bacteria.

[0146] The simultaneous use of multiple frequencies allows synergistic effects to be generated, simultaneously causing oxidative stress, direct structural damage to bacterial membranes, genetic alterations and enzyme inhibitions. The multiplicity of frequencies also makes it harder for bacteria to develop resistance mechanisms, because adapting to multiple simultaneous stimuli is complex and biologically less likely. The emiter according to the present invention exploits in particular the photodynamic action of the frequencies used, specifically promoting light absorption by bacterial chromophores. This combined mechanism is extremely effective at amplifying the overall bacterial damage.

[0147] In concrete terms, the emiter according to the present invention implements this multi-frequency approach using three distinct spectral bands, precisely with peaks at 407 nm, 413 nm and 420 nm, in the region of visible light. These specific peaks are selected for their ability to enter biological resonance, that is, to selectively stimulate target molecules typical of bacteria such as porphyrins, flavins and other chromophore proteins. Biological resonance refers to the phenomenon whereby a specific light frequency interacts specifically with a biological molecule, inducing an effective and targeted response that amplifies the antibacterial effect due to a precise and intensified action on sensitive cellular structures.

[0148] This configuration allows continuous disinfection in inhabited environments without damage or risk to human and animal health.

[0149] The adoption of the multi-peak spectrum in the technology of the present invention represents a significant technical and scientific advance over singlefrequency light sources, with optimized efficiency and lower transmited energy for the same result. This approach ensures enhanced antibacterial efficacy, high operational safety, and a significant reduction in the ability of bacteria to develop resistance.

[0150] In accordance with embodiments, the emiters 26A, 26B, 26C, e 27 are connected by gold connecting wires, not depicted, preferably gold having a purity greater than 99%, more preferably greater than 99.95%.

[0151] According to embodiments, the emiter unit 23 comprises a photosensitive coating layer 34 arranged in such a way as to enclose the primary emiters 26A, 26B and 26C and the secondary emiter 27, to modify the overall emited electromagnetic spectrum.

[0152] According to embodiments, the photosensitive coating layer 34 is configured to emit a spectrum with wavelength comprised between 400 nm and 700 nm, in which the peak values of the wavelengths XI, X2, X3 of the primary emiters 12 and possibly also the peak value of the wavelength X4 of the secondary emitter 27 are present. According to embodiments, the photosensitive coating layer 34 is made of phosphorus and is configured to modify the frequency, i.e. the wavelength of the emitted radiation, bringing it at least partially outside the specific frequency / wavelength of the respective emitter group 23, but letting pass, substantially without modifying them, i.e. without significantly affecting them, the radiations with wavelengths XI, X2, X3 generated by the primary emitters 26 A, 26B and 26C, so as to have a high disinfecting effect on the sensitive microorganisms in this band.

[0153] The adoption of the phosphor layer 34, in particular but not exclusively of the KSF (Potassium Fluorosilicate) type, combined with the special configuration of the LED emitter described above, which, in addition to the blue emitter, also integrates three distinct emitters with wavelengths centred around 407 nm, 413 rnn and 420 nm, represents a highly innovative technological solution to significantly improve the overall efficiency of the LED. This configuration makes it possible to achieve a luminous efficiency comparable to that of LEDs with colour rendering (CRI) equal to 80, while maintaining a CRI higher than 90.

[0154] The broadening of the light spectrum towards the blue-violet bands produced by the additional emitters greatly improves colour perception and visual contrast, thus enriching the quality of the emitted light. This additional spectral range allows for more effective stimulation of the S cones in the retina, which are responsible for perceiving cooler colours and subtle shades, improving overall visual acuity.

[0155] KSF phosphors, due to their extremely narrow emission spectrum centred in the red region around 630 nm, allow an increase in the luminous efficiency of radiation (LER), effectively compensating for the introduction of emissions in the Soret band (deep blue band) generated by the emitters at 407, 413 and 420 nm. This compensation in terms of colorimetric coordinates helps to create an optimal balance that enhances both energy efficiency and colour quality. The superior stability of KSF phosphors under high light intensity and high temperatures also ensures better reliability and durability.

[0156] The integration of the KSF phosphors with the deep emissions in the Soret band produced by the LED according to the present invention generates a significantly richer light spectrum than traditional LED technologies based exclusively on nitride phosphors. This light spectrum is extremely similar to natural sunlight, improving the perception of visual comfort and the feeling of well-being in indoor environments.

[0157] The use of this technological combination therefore not only makes it possible to achieve high colour rendering with high energy efficiency, but also to replicate a quality of indoor lighting that closely resembles natural light, contributing to improved quality of life and physical and mental well-being.

[0158] The emitters 26A, 26B, 26C and 27 are preferably of the high light efficiency type, preferably comprised between 120 and 200 Im / w, even more preferably comprised between 140 and 180 Im / w.

[0159] Fig. 6 illustrates the spectra of electromagnetic radiation emitted respectively by the set of three primary emitters 26A, 26B, 26C, by one or more emitter groups 23 comprising the set of three primary emitters 26A, 26B, 26C and the secondary emitter 27, or their multiples, and by one or more emitter groups 23 in combination with a phosphor coating layer 34, i.e. capable of converting blue light into white light with a continuous spectrum.

[0160] In particular, the presence of the three electromagnetic radiations having respective wavelengths XI, X2, X3 centred on peak values close to each other allows to obtain a resulting spectral emission S that covers substantially the entire Soret band, so as to be strongly effective on certain microorganisms.

[0161] With reference to Figs. 7 to 9, the disinfecting method according to the present invention substantially comprising at least one washing and / or drying step Fl, typical of the operation of the machine 10, and at least one disinfecting step F2, in which the control unit 50 starts the activation of the emitter units 23.

[0162] In the embodiments of the method according to the present invention, represented in Figures 7 and 8, the disinfecting step F2 is started with offset timing with respect to the washing and / or drying step Fl, while in the embodiment represented in fig. 9, the disinfecting step F2 is started with simultaneous timing with respect to the washing and / or drying step Fl.

[0163] In particular, in the embodiment shown in fig. 7, the disinfecting step F2 is started immediately upstream of the washing and / or drying step Fl, while in the embodiment shown in fig. 8, the disinfecting step F2 is started immediately downstream of the washing and / or drying step Fl.

[0164] Preferably, the disinfecting step F2 has a duration comprised between about 100 / 120 minutes and about 360 minutes, regardless of the operating sequence chosen by the command unit 50.

[0165] It is clear that modifications and / or additions of parts may be made to the method of the control unit 50 as described heretofore, without departing from the field and scope of the present invention, as defined by the claims.

[0166] It is also clear that, although the present invention has been described with reference to some specific examples, a person of skill in the art shall certainly be able to achieve other equivalent forms of the disinfecting method and control unit thereof having the characteristics as set forth in the claims and hence all coming within the field of protection defined thereby.

[0167] In the following claims, the sole purpose of the references in brackets is to facilitate their reading and they must not be considered as restrictive factors with regard to the scope of protection defined by the claims.

Claims

CLAIMS1. Method for disinfecting a machine (10) for washing and / or drying objects, comprising at least one washing and / or drying step (Fl) in at least one operating chamber (11) defined by a containing structure (12), a front and / or upper aperture (13) and at least one bottom wall (14), and at least one disinfecting step (F2), in which at least one emitter unit (23) cooperating with said operating chamber (11) and comprising a set of three primary emitters (26A, 26B, 26C) and at least one secondary emitter (27) is activated, wherein said primary emitters (26A, 26B, 26C) are different from each other and each configured to emit electromagnetic radiation having a wavelength with a specific peak value different from the other two primary emitters.

2. Disinfecting method as in claim 1, characterized in that said set of three of primary emitters comprises:- a first emitter (26A) configured to emit an electromagnetic radiation having a peak value with wavelength (LI) comprised between 404 rnn and 409 rnn;- a second emitter (26B) configured to emit an electromagnetic radiation having a peak value with wavelength (L2) comprised between 411 rnn and 416 nm;- a third emitter (26C) configured to emit an electromagnetic radiation having a peak value with wavelength (L3) comprised between 418 nm and 424 nm; and wherein said at least one secondary emitter (27) is configured to emit an electromagnetic radiation towards at least an internal portion of said operating chamber (11) and having a peak value with a wavelength (L4) comprised between 452 nm and 458 nm.

3. Disinfecting method as in claim 1 or 2, characterized in that said disinfecting step (F2) is started with offset timing with respect to said washing and / or drying step (Fl).

4. Disinfecting method as in claim 1 or 2, characterized in that said disinfecting step (F2) is started with simultaneous timing with respect to said washing and / or drying step (Fl).

5. Disinfecting method as in one or the other claim hereinbefore, characterized in that said disinfecting step (F2) has a duration comprised between about 120 minutes and about 360 minutes.

6. Disinfecting method as in one or the other claim hereinbefore, characterized inthat said disinfecting step (F2) is started immediately upstream of said washing and / or drying step (Fl).

7. Disinfecting method as in one or the other claim hereinbefore, characterized in that said disinfecting step (F2) is started immediately downstream of said washing and / or drying step (Fl).

8. Disinfecting method as in one or the other claim hereinbefore, characterized in that said emitter unit (23) comprises at least one electronic support (28) configured to support said set of three primary emitters (26A, 26B, 26C) and said secondary emitter (27), and at least one support element (30) positioned in direct cooperation with a housing seating (22) formed in cooperation with said operating chamber (11), and configured to house at least part of said emitter unit (23), to maintain said electronic support (28) in a specific position for emitting light radiation.

9. Disinfecting method as in claim 8, characterized in that said emitter unit (23) comprises at least one refraction element (29), positioned in direct cooperation with said housing seating (22) and configured to cooperate with said set of three primary emitters (26A, 26B, 26C) and said secondary emitter (27), to condition the refraction of the light radiation emitted onto a refraction plane (Pl).

10. Disinfecting method as in claim 9, characterized in that the conditioning of the refraction of the light radiation emitted on said refraction plane (Pl) defines a specific angle of refraction (a), with respect to an emission plane (P2) substantially orthogonal to said lateral containing structure (12).

11. Disinfecting method as in claim 9 or 10, characterized in that it provides for arranging a support element, or capsule (30), in direct cooperation with said housing seating (22), opposite the refraction element (29) and configured to maintain said electronic support (28) in a certain position of emission of the light radiation, towards the inside of the operating chamber (11).

12. Disinfecting method as in claim 11, characterized in that it provides that said refraction element (29) and said support element (30) cooperate elastically with each other, by means of relative snap coupling members (31).

13. Control unit (50) for a machine (10) for washing and / or drying objects, comprising at least one operating chamber (11) defined by a containing structure (12), by a front and / or upper aperture (13) and by at least one bottom wall (14),characterized by at least one emitter unit (23) housed in said operating chamber (11) and comprising a set of three primary emitters (26A, 26B, 26C) and at least one secondary emitter (27), wherein said primary emitters (26A, 26B, 26C) are different from each other and each configured to emit an electromagnetic radiation having a wavelength with a specific peak value different from the other two primary emitters.

14. Control unit as in claim 13, characterized in that said primary emitters (26A, 26B, 26C) comprise:- a first emitter (26A) configured to emit an electromagnetic radiation having a peak value with wavelength (XI) comprised between 404 nm and 409 nm, preferably 407 nm;- a second emitter (26B) configured to emit an electromagnetic radiation having a peak value with wavelength (X2) comprised between 411 nm and 416 nm, preferably 413 nm;- a third emitter (26C) configured to emit an electromagnetic radiation having a peak value with wavelength (X3) comprised between 418 nm and 424 nm, preferably 420 nm; and wherein said at least one secondary emitter (27) is configured to emit an electromagnetic radiation having a peak value with a wavelength (X4) comprised between 452 nm and 458 nm.

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