FR2877845A1 - METHOD FOR IMPROVING ODOR DIFFUSION TECHNIQUES - Google Patents

Abstract

The invention relates to a method and a device for improving the diffusion of single-scent or multi-scent odors with a view to improving the perception thereof. The method is applicable to any device known from the state of the art provided that the latter has the capacity to control the intensity of the diffusion of odorous molecules. This control is carried out by controlling the air flow causing the odorous molecules.

Description

PROCESS FOR IMPROVING TECHNIQUES

OF ODOR DISSEMINATION

  The present invention relates to the field of odor diffusion.

  The invention relates to a method and a device for improving the diffusion of mono-scented or multi-scented scents with a view to a better perception thereof. The method is applicable to any device known in the state of the art since it has a capacity to control the intensity of diffusion of odor molecules. This control is effected for example through the control of the air flow resulting odor molecules.

  The invention more particularly relates to a method for diffusing odors intermittently so as to allow the time, between two successive diffusions, for the enzymes present in the mucous membrane of the nose to eliminate the odorant molecules, which makes it possible to avoid the fall of perception in time of the smell.

  The olfaction is that of the five human senses that allows the perception of odors. An odor is characterized by a combination of molecules that propagate in the air and reach the olfactory receptors of the nose. When an odor disappears from the environment elimination of odor molecules from their receptor sites is provided by enzymes present in the olfactory mucosa, a kind of vigils responsible for ridding the receptors of odor molecules.

  Various methods and devices are known for diffusing odors. One of the main techniques is based on the use of porous materials impregnated with odorous molecules or materials partially made of such molecules, materials that are passed through or licked by a stream of air. Another known technique is 2877845 2 based on the use of olfactory liquids which are vaporized by micronization.

  For example EP01212104B1 discloses a perfume diffusion device based on a flow of air passing through a soaked material. This device is controlled by a digital television set or a microcomputer. Another example of a known device is described by patent EP01054697B1. This device makes it possible to sequentially diffuse several perfumes with the particularity of avoiding the remanence during a change of perfume thanks to a capacity of hermetic sealing of the perfume tanks that one does not wish to diffuse.

  The present invention intends to overcome the drawbacks of the prior art by proposing a method and a device for diffusing odors. It provides a solution to two known problems of odor diffusion. The first problem is that the olfactory sensation perceived by a human being subjected to a permanent odor environment diminishes and even disappears after a certain time. The second problem is that the number of molecules emitted decreases over time in the case of use of substances soaked because of the gradual drying of the latter.

  The process according to the present invention is particularly suited to the future expectations of odor diffusion devices in medium-sized spaces, for example a restaurant room, in that the odors are perceived without deterioration of the olfactory perception of the users .

  For this purpose, the invention relates in its most general sense to a method of diffusion of an odor characterized in that the diffusion is carried out intermittently in order to allow time, between two successive diffusions, the enzymes present in the mucosa from the nose to eliminate the odorous molecules, which makes it possible to avoid the decrease of perception in the time of the smell.

  In one embodiment concerning the diffusion of several different odors, the diffusion of each of the odors taken individually is carried out intermittently in order to allow the time, between two successive diffusions of the same odor, to the enzymes present in the mucous membrane of the nose. to eliminate the molecules corresponding to this odor, which makes it possible to avoid the decrease of perception in time of each of the smells.

  In a particular embodiment, the periods of diffusion of different odors are juxtaposed or overlap, which makes it possible to diffuse at least one odor at any time.

  The invention also relates to a method for diffusing an odor in which materials impregnated with odorant molecules are subjected to a flow of air for diffusing the odorant molecules, characterized in that the airflow is increased over time. in order to maintain substantially constant flow of fragrant molecules diffused despite the gradual drying of the soaked materials.

  In one embodiment, the airflow required to maintain the flow of molecules substantially constant is determined as a function of the state of drying of the impregnated materials reevaluated in real time during the period of diffusion of the odor.

  In a particular embodiment, the determination of the required airflow as a function of the state of drying of the impregnated materials is carried out using a table of data entered during the design of the diffusion device. 'odour.

  According to one embodiment, the dewatering state 35 is evaluated in real time during the operation of the diffusion device 2877845 4, by means of a function chosen during the design thereof, a function whose variables are the previous state of drying, the air flow from this previous state, and the time separating the new state from this previous state.

  In one embodiment, the function is a polynomial function.

  According to another embodiment, the dewatering state is evaluated in real time during the operation of the diffusion device by using a measuring device comprising sensors adapted to different odors.

  The present invention also relates to a method for diffusing a plurality of odors in which materials impregnated with odorant molecules are subjected to a flow of air for diffusing the odorant molecules, characterized in that, for each of the odors considered individually, the air flow rate is increased from one diffusion period to another in order to keep the flow of diffusing odorous molecules substantially constant despite the progressive drying of the impregnated materials.

  The present invention also relates to a device for diffusing a plurality of odors, characterized in that the diffusion of each of the odors taken individually is carried out intermittently in order to allow time, between two successive diffusions of the same odor, to enzymes present in the mucosa of the nose to eliminate the molecules corresponding to this odor, and in that the air flow is increased from one diffusion period to another in order to maintain substantially constant the flow of odorous molecules diffused despite gradual drying of soaked materials.

  The invention will be better understood from the following description, given for purely explanatory purposes, of one embodiment of the invention, with reference to the appended figures: FIG. level of the olfactory sensation perceived by a user placed in a continuous flow of odorous molecules fl, f2 or f3. The flow is equal to the number of molecules released per unit of time. fl is less than f2, and f2 is less than f3. The graph shows that the olfactory sensation increases as the flow increases. It shows above all that the olfactory receptors of the nose are saturated and that the perception decreases suddenly once saturation is reached.

  FIG. 2 represents the appearance of the level of perceived olfactory sensation when the flow of odorant molecules is diffused discontinuously, with durations between two successive diffusions sufficient for the olfactory receptors of the nose to have time to return to their initial state . As a result, the olfactory receptors of the nose never reach saturation.

  Figure 3 shows the appearance of the olfactory sensation obtained during a diffusion of three different odors, each diffused discontinuously so as never to saturate the olfactory receptors. The three smells are diffused in turn which makes that at any time one or the other of the smells is diffused. Recall that it is known that the operation of the human nose is such that the odors are treated almost independently of each other with respect to the saturation of olfactory receptors in particular.

  Figure 4 shows the appearance of the flow of odorous molecules diffused under the effect of three different air flows through materials soaked odor molecules. The graph shows that the flow of diffused odor molecules increases as the airflow increases. It shows above all that the flow of odorous molecules decreases with time under the effect of a gradual drying of the soaked materials.

  Figure 5 shows the flow rate of 5 odorant molecules over time when increasing the air flow to compensate for the decrease in the flow of molecules due to dewatering materials. Finally, the flow can be maintained at any time between a high threshold and a low threshold.

  FIG. 6 shows a table structure allowing at any time to define the air flow rate necessary for the flow of odorant molecules to reach the high threshold as a function of the level of drying of the impregnated materials.

  Figure 7 shows the shape of the flow of odorant molecules over time with a method avoiding both the saturation of the olfactory mucosa and the decrease in the flow of molecules due to the drying of the materials with time.

  FIG. 8 shows an embodiment of the invention for diffusing a plurality of odors in which each of the materials impregnated with odorous molecules is subjected to an intermittent flow of air, with, in addition, a capacity for increasing the air flow to maintain substantially constant flow of fragrant molecules diffused despite the gradual drying of the soaked materials.

  It is known that the perception of an odor by a person decreases in case of prolonged exposure because there is adaptation in the treatment of information by the central nervous system as soon as the olfactory receptors reach a certain level of saturation, feedback mechanism that favors the perception of odor changes. This decrease occurs relatively abruptly over time, as shown in FIG. 1. It is also known that this decrease in perceptive perception of a persistent odor does not affect the sensitivity to the others. odors. When an odor disappears from the environment, an elimination of odor molecules from their receptor sites of the nose is provided by enzymes present in the olfactory mucosa, sort of vigils responsible for ridding the receptors of odor molecules previously captured, which restores after for a certain time the perception capacity of the odor considered if it reappears later.

  The first aspect of the process according to the invention, applicable to all odor diffusion devices with a capacity for controlling the diffusion of odor, is intended to avoid saturation of the olfactory receptors of the nose. It consists of diffusing the odor molecules not continuously but intermittently, as shown in FIG. 2, in order to allow time for the action of the enzymes between two periods of odor diffusion. During this period of no diffusion of an odor it is possible to diffuse either no smell or another smell, which will also be diffused intermittently to avoid saturation olfactory receptors on this other smell. It is also possible to permanently diffuse odors without causing saturation when different smells are emitted each intermittently and the diffusion of a new odor starts before or when stopping the diffusion of the previous odor , as shown in Figure 3. A variant is to diffuse the same odor continuously but alternately to the right of the viewer and then to the left, to alternately activate the olfactory mucosa of the right nostril and those of the left nostril, the unactivated nostril enjoying a period of saturation when the other perceives the odor.

  The second aspect of the process according to the invention is applicable to odor diffusers comprising materials impregnated with odorant molecules. An example of impregnated material is PEBAX, a Polyether Block Amides from ATOFINA. It is a polymer that can adsorb a large amount of odorant molecules. Also used in this document the qualifier impregnated for the case of materials that are composed of odorous molecules tending to separate from each other and to vaporize which leads to the gradual disappearance of the material. In order to respond to the problem of the decrease over time of the quantity of odorous molecules emitted due to the gradual drying of the materials, as shown in FIG. 4, the process according to the invention consists in progressively increasing the air flow rate resulting odorous molecules to compensate for the effects of desiccation. Thanks to a good adjustment of the air flow, the number of molecules emitted per unit of time, and therefore the flux thereof, remains substantially constant, as illustrated in FIG. 5. To know at any time the necessary air flow rate the control means of the odor diffusion device refers for example to a data table, as shown in Figure 6, in which is indicated the required flow rate according to the state of drying imbibed materials. The information of this table is made during the design of the device from results of measurements of the flow of odorous molecules diffused according to the state of drying of the materials. This state of desiccation can be evaluated at any time by a computation unit integrated in the odor diffusion device according to the air flow rates emitted previously and the emission times. The formula for calculating the state of drying is defined during the design of the device from measurements of the drying speed of the impregnated materials as a function of the state of drying in course, of the air flow applied and the duration of diffusion of this flow. The formula for calculating the state of desiccation also takes into account the impregnated material used, in particular the contact surface of this material with air. With the realistic hypothesis that the drying behavior of soaked materials under the effect of a flow of air is repetitive and therefore predictable, it is always possible to design an equation that will make it possible to evaluate during operational operation the state En desiccation of the materials according to a state of previous drying E, _1, the air flow rate to which the material has been subjected since this previous state, and the diffusion time of this air flow.

  If we denote by Et_1 the drying state of the materials at time t-1, by dt the air flow between the hours t-1 and t, and by Dt the duration of this diffusion, the state Et is a function of Et_1, dt and Dn whose form and parameters are fixed during the design of the device by analysis or by measurements. In particular, it is known that it is always possible to determine a polynomial equation more or less accurately accounting for measurement results. Of course, instead of this equation, it is always possible to use a given table, but it may in this case be relatively complex since it has three inputs: previous state, airflow, duration of diffusion.

  Depending on the design of the device a simple polynomial may be sufficient to account for the evolution of the drying state. For example, the state Et may in some cases be approximated by the product of a constant k multiplied by Et_1 and then divided by dt and by Dt, where k is specific to the design of the broadcasting device.

  This real-time knowledge of the dewatering state of the impregnated materials enables the device, by virtue of the table, to calculate the air flow rate necessary for the flux of scattered odorant molecules to remain substantially constant.

  It is also possible to control the air flow not according to the estimate of the current state of dewatering but as a function of a real-time measurement of the flow of odorous molecules actually emitted. Such a device, however, requires the design of sensors adapted to different odors, so leads to complex technical designs.

  The method according to the invention consists in combining the two aspects described above in order to obtain a perception of odors both without risk of olfactory saturation and on the other hand constant over time.

  With this method, the diffusion of the same odor is carried out intermittently and the calculation of the state of drying is advantageously carried out at the beginning or end of each diffusion period. If we denote by En_1 the state of drying of the materials at the end of the (n-1) ith period of diffusion of odor, by dn the air flow during the period of diffusion n, and by In the duration of this diffusion, the state En is a function of E, _1, dn and Dn.

  An example of a device embodying the method according to the invention presented will now be described, with reference to FIG. 8. The device comprises a control member (1), a turbine (2), a plurality of cartridges (3a) , (3b), (3c), .. each containing particles of material impregnated with odorant molecules, solenoid valves (4a), (4b), (4c), .. The control member (1) calculates at any time the flow rate necessary to keep constant the flow of odorant molecules to diffuse. It performs this calculation using an estimate of the state of drying of the materials, in accordance with the method described above, and according to the content of the table indicating the required flow rate according to the state of drying 2877845 11 soaked materials. The control member (1) sets the voltage applied to the turbine (2) according to the required flow. It also controls the solenoid valves (4a), (4b), (4c), .. so as to circulate the pulsed air by the turbine in the odor to be diffused and only in it. In Figure 8 the air circulates in the odor cartridge (4a). The control member (1) controls, if necessary, the start-up and shutdown of the turbine (2), so that the diffusion of each of the odors is intermittent in order to avoid saturation of the olfactory receptors nose 2877845 12

Claims (13)

  1. A method of diffusing odors for nose recovering a smell perception capacity after a threshold time, characterized in that it comprises alternating stages of diffusion and non-diffusion of a first odor the duration of a step of non-diffusion of the odor being at least equal to said threshold time.   2. A diffusion method according to claim 1, characterized in that it further comprises alternate steps of diffusion and non-diffusion of at least one second odor, the duration of a step of non-diffusion of the second odor being at least equal to said threshold time.   3. The diffusion method according to claim 2 characterized in that said diffusion steps of the different smells are juxtaposed.   4. Diffusion method according to claim 2 characterized in that said steps of diffusion of different smells overlap.   5. Diffusion method according to claim 1, characterized in that it comprises a step of supplying an air flow on materials soaked with odorant molecules, the air flow being increased over time.   6. A method of diffusion according to claim 5, characterized in that it further comprises a step of calculating the state of drying of said impregnated materials and a step of determining said air flow rate as a function of said state of drying. 30   2877845 13 7. Broadcasting method according to claim 6, characterized in that the step of determining the air flow rate is to determine said air flow using a data table entered during the design of the device. odor diffusion.   8. Broadcasting method according to claim 6 or 7, characterized in that, during said step of calculating the state of drying, said drying state is calculated in real time depending on the state of drying previously calculated previous, the air flow from this previous state, and the time separating the new state from this previous state.   9. The diffusion method according to the preceding claim, characterized in that the relationship for calculating the drying state as a function of the prior drying state, the air flow rate and the duration is a polynomial function.   10. A diffusion method according to claim 6 or 7, characterized in that it further comprises a step of measuring in real time the flow of odorant molecules by sensors adapted to different odors, and in that, when said step of calculating the dewatering state, said dewatering state is evaluated in real time as a function of the flow of molecules measured.   11. A method of diffusion according to claim 5, characterized in that, for each of the odors considered individually, the air flow is increased from one diffusion period to another to maintain substantially constant flow of fragrant molecules scattered.   2877845 14 12. Odor diffusion method according to claim 1, characterized in that, during the steps of diffusion of an odor, the diffusion is carried out on a side of a spectator, for example the right, and in that it comprises, additional steps of diffusion and non-diffusion of the same odor, the diffusion being performed on another side of the viewer, for example the left, said steps and additional steps being alternately performed.   13. Device for diffusing a plurality of odors for carrying out the method according to one of the preceding claims, comprising a plurality of odor cartridges (3a, 3b, ...), diffusion means ( 2, 4a, 4b, ...) and control means (1), said control means (1) controlling said diffusion means (2, 4a, 4b, ...).