FR2835765A1 - DEVICE FOR DIFFUSING A LIQUID IN THE ATMOSPHERE INCORPORATING MEANS FOR CLEANING A SPRAY NOZZLE - Google Patents

Abstract

The invention relates to a device for diffusing a liquid into the atmosphere in the form of droplets, comprising at least one reservoir (1) containing a liquid (2) to be diffused, diffusion means comprising a spray nozzle (5) , means (7) for generating a propellant gas flow passing longitudinally through said spray nozzle and an inlet duct (3) into said nozzle of the liquid contained in the reservoir. The device is characterized in that it comprises means for unblocking the spray nozzle comprising a unblocking rod (14) adapted to be able to be moved in longitudinal translation inside the spray nozzle (5) in view of '' tear off any deposits formed on the internal walls of a critical zone from there spray nozzle, and actuation means (18, 12, 15) capable of moving the unblocking rod between a diffusion position and a uncorking.

Description

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DEVICE FOR DIFFUSING A LIQUID INTO THE ATMOSPHERE
INCORPORATING CLEANING MEANS
OF A SPRAY NOZZLE
The invention relates to a device for diffusing a liquid into the atmosphere, such as a diffuser for perfume, odor neutralizing product or bactericidal product, intended for hospitals, stations, airports, large surfaces, etc., an agricultural sprayer, a nebulizer such as those used in the medical field, or other atomizer, aerosol, spray or mist. The diffusion device comprises a reservoir of liquid to be diffused, a spray nozzle traversed longitudinally by a propellant (gas), a conduit for admitting said liquid into said nozzle.

 After a certain number of hours of operation, it is often found that such a spray nozzle becomes clogged due to the formation and accumulation of solid deposits on its internal walls. In the case of a spray nozzle of the so-called venturi type (comprising a convergent duct then a divergent duct), the solid deposits are formed mainly opposite an area of smaller internal section of said nozzle, called the critical area (with the intersection of the converging duct and the diverging duct). These solid deposits, composed of particles resulting from the drying on the walls of droplets of the liquid to be diffused and / or of particles of dust or other impurities, are formed more or less rapidly depending on the composition of the liquid to be diffused (in particular, the presence of crystalline compounds promotes the formation of solid deposits), the quality of the propellant fluid (more or less charged with impurities), the surface condition (roughness in particular) of the internal walls of the spray nozzle in contact with the liquid to diffuse, of the possible reaction of said liquid with the propellant fluid in a low pressure area subject or not to turbulence.

 The formation of these solid deposits also depends on the arrangement, relative to the spray nozzle, of the inlet conduit for the liquid to be diffused - and in particular the location of its outlet orifice in said nozzle. Two main modes of relative arrangement of the intake duct and the nozzle

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 spraying is possible: a first mode, called spray nozzle with lateral intake duct, in which the intake duct opens at the critical zone of the spray nozzle, forming, with the longitudinal direction of said nozzle, an angle between 45 and 90 for example; and a second mode, called spray nozzle with axial intake duct, in which the intake duct has an outlet orifice situated in a central axis and upstream of the critical zone of the spray nozzle, said duct is preferably extending (at least over a downstream portion) parallel to the longitudinal direction of the spray nozzle. It can be seen that a spray nozzle with an axial intake duct clogs faster and more frequently than a spray nozzle with a lateral intake duct.

 To overcome these drawbacks, several approaches have been considered.

 Certain known devices incorporate a needle permanently arranged in the spray nozzle. Thus, FR 979.385 describes a spraying device comprising a spray tip defining a chamber upstream of a spray duct, said chamber containing a spring secured to a needle engaged in the spray duct. To dislodge a solid body obstructing the conduit, one exerts a pressure with the nail on the end of the needle in order to make slide this one in the conduit, thus to take off the solid body and to allow its drive by the flow of liquid to spray.

 Other known devices use the pressurization gas of the liquid to be diffused to prevent the spray nozzle from clogging. Thus, US-3,951. 314 describes a device for diffusing a pressurized liquid, provided with a valve which can be moved manually between a diffusion position, in which it lets the fluid to diffuse through, and a cleaning position closing the intake duct of the liquid, in which the valve allows the pressurization gas to pass through the liquid.

 Another prior approach has consisted in choosing, in order to produce the elements of the diffuser - and in particular the spray nozzle - in contact with the liquid to be diffused, materials or surface treatments capable of limiting the formation of deposits. FR 2,756. 502 describes a spray nozzle whose surface portions in contact with the liquid to be diffused are covered with a material with a low coefficient of friction, and

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 in particular of a xylylene polymer deposited under vacuum under a ton of a homogeneous lilm from 1 to 5 u. m thick. EP-768,921 describes an atomization system comprising a spray nozzle produced from a reduced wettability composition comprising a base material, comprising for example polyoxymethylene, and a wettability reducing component, comprising a molten additive consisting of silicone, polytetrafluoroethylene or other fluorinated chemicals, so that the liquid to be diffused is repelled by the surfaces of the spray nozzle.

 However, these different approaches have not been entirely satisfactory. The device described by FR 979.385 makes it possible to dislodge a solid body wedged between the needle and the internal wall of the spray duct and to help detach particles loosely attached to said wall, but is of limited effectiveness in the face of deposits more strongly bonded or even encrusted on the wall. Likewise, the gas for pressurizing the liquid used by US Pat. No. 3,951,314 remains insufficient to remove such deposits. The materials provided by FR-2 756 502 or EP-768 921 slow the formation of solid deposits on the walls of the nozzle without completely preventing it. So the known nozzles inevitably end up clogging.

 The invention aims to provide a device for diffusing a liquid into the atmosphere in the form of droplets, incorporating means for unblocking each spray nozzle of the device, capable of effectively and safely peeling off any deposits formed on internal walls of said spray nozzle, and in particular on the internal walls of the nozzle - or portions of said walls - opposite a critical zone of smaller internal section of the spray nozzle.

 Another objective of the invention is to propose means for unblocking the spray nozzle (s) of a diffusion device, which are adapted to various types of spray nozzle (nozzles with lateral intake duct and nozzles with axial intake duct).

 The invention also aims to propose means for minimizing the formation of solid deposits in such a spray nozzle, and in particular in the critical zone of smaller section of said nozzle.

 Another objective of the invention is to propose a device for diffusing a liquid into the atmosphere incorporating means for unclogging the

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 liquid intake pipe to be dispersed. The invention aims in particular to propose common unblocking means capable of unblocking both the spray nozzle and the intake duct.

 Another objective of the invention is to provide a diffusion device incorporating means for automatic actuation of the means for unblocking the spray nozzle and / or the fluid intake duct in the event of said spray nozzle being blocked. and / or said conduit, and / or the formation and / or accumulation of solid deposits in said spray nozzle and / or said conduit.

 The invention relates to a device for diffusing a liquid into the atmosphere in the form of droplets, comprising: at least one reservoir containing a liquid to be diffused, for each reservoir, means for diffusing into the atmosphere the liquid contained in the reservoir, comprising a spray nozzle, means for generating a propellant gas flow passing longitudinally through said spray nozzle, and a conduit for admitting the liquid contained in the reservoir into said nozzle, opening upstream or facing '' an area of smaller internal section of the spray nozzle, called the critical area, (and downstream of an inlet orifice in the spray nozzle for the propellant flow), - said diffusion means being capable of allowing formation droplets of liquid from the reservoir (the spray nozzle comprises, for example, a throttle, defining a critical low-pressure zone; the passage of the propellant flow in viewing the outlet opening of the intake duct causes the liquid to be sucked in and mixed with the propellant flow; the expansion of the liquid at the critical zone causes the formation of microdroplets).

 The device according to the invention is characterized in that it comprises, for each spray nozzle, means for unblocking said spray nozzle comprising: * a unblocking rod adapted to be able to be moved in longitudinal translation inside the spray nozzle in order to remove any deposits formed on the internal walls of the spray nozzle in the critical zone; in particular, the unblocking rod has a section (variable or constant) less than or equal at all points to the smallest internal section of the nozzle.

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 spraying so as to be able to slide in said nozzle; it preferably has a constant section at least substantially identical to said smaller internal section, * actuating means capable of moving the unblocking rod between a position, called the diffusion position, in which the rod extends to the outside of the spray nozzle, at a distance from an outlet orifice of said spray nozzle so as to allow diffusion, and a position, known as the unclogging position, in which the unblocking rod extends inside the spray nozzle, through the critical area.

 It should be noted that: for each spray nozzle, the propellant gas flow is introduced into the spray nozzle through an inlet orifice of said nozzle so as to flow generally substantially in a longitudinal direction of the spray nozzle, then escape loaded with microdroplets of fluid through an opposite outlet orifice of said spray nozzle. The terms “upstream” and “downstream” are used relative to the direction of flow thus defined by the propellant flow through the spray nozzle, - the diffusion device is preferably adapted to receive a plurality of reservoirs, in particular removable. Advantageously and according to the invention, part of the diffusion means (means for generating propellant flow and / or spray nozzle) may be common to different tanks. In all cases, the term "means for diffusing the liquid contained in a reservoir" means the diffusion means (spray nozzle, means for generating propellant flow and intake duct) associated, in operation, with said reservoir. The expression "activate", respectively "inhibit", "the means of diffusion of the liquid contained in a reservoir" means activate, respectively inhibit, at least part of the diffusion means associated with said reservoir so as to authorize, respectively prohibit, the diffusion in the atmosphere of the liquid contained in the tank. In particular, in the case of a diffusion device comprising a single air pump (means for generating propellant flow) and a plurality of removable cartridges each comprising a reservoir and a spray nozzle connected by an intake duct, the means of diffusion include means of distribution (conduits and valves), in the various spray nozzles, of the propellant flow generated by the air pump. The term "activate"

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 respectively "inhibit", "the means of diffusion associated with a cartridge (or a reservoir)" then means "open", respectively "close", a valve supplying a propellant flow to the spray nozzle of said cartridge, in the same way , different spray nozzles can advantageously share common unblocking means, the actuation means being in this case adapted to position the unblocking rod opposite the spray nozzle to be unblocked before its introduction into said spray nozzle. The "unclogging means" unambiguously denote those associated with the spray nozzle considered, - the critical zone is defined as the zone of smallest internal section located downstream of the outlet orifice of the intake duct, this which does not exclude the possibility that the spray nozzle has, at a point upstream of said outlet orifice of the intake duct, an internal section smaller than that of said critical zone.

 Advantageously and according to the invention, the diffusion device comprises, for each intake duct and / or spray nozzle, means for unblocking the intake duct, comprising means for closing (preferably sealed) the outlet orifice of the spray nozzle to allow delivery to the tank, by means of the propellant, the liquid and any particles present in the intake duct.

 In particular, the shutter means comprise: a shutter cover for the outlet orifice of the spray nozzle, means for arranging the shutter cover, capable of moving said shutter cover between a position of diffusion, at a distance from the outlet orifice of the spray nozzle so as to allow the diffusion, and a shutter position, in which the shutter cover is in abutment against the outlet orifice of the spray nozzle with a view to filling it.

 Advantageously and according to the invention, the diffusion device comprises control means, for example electronic, capable of controlling, for each spray nozzle and / or intake duct, the means for generating propellant flow, the means for actuation of the drain rod (or part of the said

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 means) and, where appropriate, the means for arranging the shutter cover (or a part of said means). Note that the unblocking means are also advantageously adapted to be able to be actuated manually.

 In the case of a spray nozzle with a lateral intake duct, the control means are preferably adapted to control said means for generating propellant flow, said means for actuating the unblocking rod and said means for arranging the shutter cover so as to control the propellant flow generated and move the unblocking rod and the shutter hood according to a unblocking cycle comprising the following chronological steps: - if necessary, positioning the unblocking rod and the hood d sealing in the diffusion position, - displacement of the unblocking rod from its diffusion position to its unclogging position, with a view to removing, by means of the unblocking rod, any deposits formed on the internal walls of the spray nozzle in the critical zone, displacement of the unclogging rod from its unclogging position to its diffusion position, - displ acement of the shutter cover from its diffusion position to its shutter position, - generation of a propellant flow, preferably of high flow - greater than a nominal diffusion flow and for example close to the maximum flow that can be generated by the propellant flow generation means when they operate at a maximum authorized speed - in the case of variable flow flow generation means, for a predetermined period of time, with a view to pumping back to the tank, by means of the propellant gas, the liquid and any particles present in the intake duct, - if necessary, displacement of the shutter cover from its shutter position to its diffusion position, and generation of a propellant flow according to a nominal diffusion regime (defined by a nominal diffusion rate or a nominal diffusion frequency according to the mode of regulation of the flow generation means).

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 In the case of a spray nozzle with an axial intake duct, advantageously and according to the invention: - the shutter cover is carried by a downstream end of the unblocking rod so that there is a common position the unblocking rod and the closure cap, known as the diffusion position, in which the unblocking rod and the closure cap are spaced from the outlet orifice of the spray nozzle so as to allow diffusion, and a common position of the unblocking rod and the closure cap, known as the unblocking position, in which the closure cap is in abutment against the outlet orifice of the spray nozzle with a view to its obturation and the rod unblocking extends inside the spray nozzle, through the critical zone, and has an upstream end at a distance from an outlet orifice of the intake duct, the means for actuating the unblocking rod serve as a hub ens of cover arrangement.

 Advantageously and according to the invention, the control means are then preferably adapted to control the propellant flow generation means and the actuation means so as to control the propellant flow generated and move the unblocking rod and the shutter cover. according to a unblocking cycle comprising the following chronological steps: - if necessary, positioning (joint) of the unblocking rod and of the closure cap in the diffusion position, - displacement (joint) of the unblocking rod and of the hood d sealing from the diffusion position to the unclogging position, with a view to removing, by means of the unblocking rod, any deposits formed on the internal walls of the spray nozzle in the critical zone, - generation of '' a propellant flow, preferably with a high flow rate, for a predetermined period of time, with a view to discharging towards the reservoir, by means of the propellant gas, the liquid and any particles present in the intake duct, - if necessary, displacement (joint) of the unblocking rod and the shutter cover from the unclogging position to the diffusion position, and generation of a propellant flow according to a nominal diffusion regime.

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 It should be noted that, in the case of a spray nozzle with lateral intake duct as in that of a nozzle with axial intake duct, during the phases of positioning the rod and the cover in the diffusion position , displacement (concomitant or not depending on the case) of the rod to its uncorking position and the cover to its uncorking or sealing position, reverse displacement of the rod and the cover to their position diffusion, the control means are adapted to activate the means for generating propellant flow according to a nominal diffusion regime or, alternatively, a high regime or, alternatively, inhibit said means.

 Advantageously and according to the invention, in the case of a spray nozzle with an axial intake duct, the unblocking rod (associated with said nozzle) preferably has a suitable upstream end (by its shape and / or its constituent material ) to be able to seal the outlet orifice of the intake duct, preferably in a sealed manner. The actuating means are further adapted to be able to move said unblocking rod between its diffusion position, its unclogging position and an extreme upstream position, called the closed position, in which the upstream end of the unclogging rod is in abutment against the outlet orifice of the intake duct in order to close it. The unblocking rod can thus be used to isolate the spray nozzle from the reservoir, and thus make it possible to transport the device (or a removable part of the device comprising at least the reservoir and the spray nozzle) without risking spilling part of the contents. of the reservoir in the spray nozzle (the spilled liquid can no longer be sprayed thereafter) and permanently damaging or clogging said spray nozzle.

 Advantageously and according to the invention, the closure cover (carried by the downstream end of the unblocking rod) then preferably comprises a flexible peripheral lip, capable of being elastically deformed so as to close the outlet orifice of the spray nozzle in the unclogging position and to allow additional movement of the unblocking rod to its closed position by crushing the peripheral lip against the outlet orifice of the spray nozzle.

 In other words, the shutter cover is designed and mounted on the unblocking rod, so that:

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 there is a common position that u uslon ae tlge ae uncorking and the shutter cover, - there is a common position unclogging the unblocking rod and the shutter cover, in which the peripheral lip of the shutter cover is in abutment against the outlet orifice of the spray nozzle and closes said orifice, and the rod extends inside the spray nozzle, through the critical zone, the upstream end of the rod remaining at distance from the outlet opening of the intake duct to allow the outlet of said duct by means of the propellant flow, - there is a position for closing the unblocking rod, in which the peripheral lip of the shutter cover is resiliently pressed against the outlet orifice of the spray nozzle, and the upstream end of the rod is in abutment against the outlet orifice of the intake duct in order to close it.

 Advantageously and according to the invention, the control means are adapted to trigger periodically, automatically, the execution of a unblocking cycle for each spray nozzle and / or intake duct.

 Advantageously and according to the invention, as a variant or in combination, for each spray nozzle and / or intake duct, the control means are adapted to trigger, automatically, the execution of a cleaning cycle after a predetermined period of non-use of said spray nozzle and / or said intake duct.

 As a variant or in combination, for each spray nozzle and / or intake duct, the control means are adapted to trigger the execution of a unclogging cycle upon reception of a corresponding signal emitted by communication means d information to the control means by a user, called user control means. Said user control means comprise for example a touch screen and / or a keyboard and / or contactors (buttons) of function, integrated in the device or in a remote control, and / or means of remote communication such as a modem , notably using the Internet.

 As a variant or in combination, the device comprises, for each spray nozzle, means for detecting an accumulation of solid deposits on the internal walls of said spray nozzle, capable of transmitting to the control means a signal indicative of a accumulation of solid deposits in said

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 spray nozzle, on reception of which the control means are adapted to trigger the execution of a cleaning cycle of said spray nozzle.

 Advantageously and according to the invention, the device comprises, for each spray nozzle, an air pump (or compressor, which can be shared between several spray nozzles, etc.) power-controlled by the control means. The power supply of said pump being imposed by the control means, the accumulation of solid deposits in the spray nozzle, and therefore the reduction of the effective internal section of the critical zone or the total closure of this section, result in an increase in the inlet pressure of the spray nozzle. The detection means advantageously comprise pressure sensor means capable of emitting, intended for the control means, a signal indicative of an accumulation of solid deposits if the pressure at the inlet of the spray nozzle is greater than a characteristic predetermined threshold value. an accumulation of solid deposits in said spray nozzle. Said detection means comprise for example a pressure switch, calibrated at said pressure threshold value. As a variant, they comprise means for measuring the pressure at the inlet of the spray nozzle, means for comparing the pressure measured with the threshold value, and means for transmitting a signal indicative of an accumulation of solid deposits. if the pressure measured is greater than the threshold value.

 The increase in the inlet pressure of the spray nozzle, due to an accumulation of solid deposits in said nozzle, also results, in the case of an electric air pump, by an increase in the current consumed by said pump. As a variant or in combination, the detection means advantageously comprise means for measuring the intensity of the supply current of the air pump, capable of emitting, intended for the control means, a signal indicative of an accumulation of solid deposits if the intensity measured is greater than a predetermined threshold value characteristic of an accumulation of solid deposits in said spray nozzle. Such detection means are preferably integrated into the control means.

 Advantageously and according to the invention, the control means are adapted to inhibit the means for generating propellant flow associated with a spray nozzle, and transmit, intended for means of communication of information to a

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 user, so-called user information means, a signal representative of an operating error, if they receive a signal indicative of an accumulation of solid deposits in said spray nozzle, immediately after (i.e. within a few seconds or a few minutes of) the execution of a predetermined number of unblocking cycles of said nozzle immediately consecutively (cycles executed a few seconds or a few minutes apart).

 Note that the user information means include, for example, a display screen (on the device or on a remote control or on a remote computer capable of communicating with the device via a modem and an intranet or internet network) and / or means of '' sound and / or light emission and / or a printer and / or remote communication means (modem and communication network), etc. The user control means and the user information means form a human interface.

 Advantageously and according to the invention, for each spray nozzle, the control means are suitable for: triggering the execution of a unblocking cycle following a command to power up the device, activating the actuation means so to arrange the unblocking rod in the closed position following a command to power off the device.

 Advantageously, each spray nozzle of the device according to the invention has, at least opposite the critical zone, internal walls with low roughness factor, in order to minimize the formation of solid deposits on these walls. In particular, the device comprises one (or more) spray nozzle (s) of injected synthetic material, produced from an impression having undergone electrolytic polishing and / or superfinishing at least on a surface delimiting the critical zone . As a variant, the device comprises one (or more) spray nozzle made of synthetic material or of machined stainless steel, having undergone electrolytic polishing and / or superfinishing at least on internal walls (or portions of walls) facing the critical area.

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 As a variant or in combination, each spray nozzle has internal walls coated, at least opposite the critical zone, with a coating with a low coefficient of adhesion of the Teflon type.

 The invention also relates to a diffusion device, characterized in combination by all or some of the characteristics mentioned above and below.

 Other objects, characteristics and advantages of the invention will appear on reading the following description which refers to the appended figures representing preferential embodiments of the invention given solely by way of nonlimiting examples, and in which: FIG. 1 is a block diagram of an embodiment of a diffusion device according to the invention, FIGS. 2 to 4 are schematic views of a spray nozzle and of uncorking means according to the invention, part of which is seen in longitudinal section, the unblocking means being respectively in the position of diffusion, closing and unclogging.

 The diffusion device illustrated in FIG. 1 comprises a reservoir 1 containing a liquid to be diffused 2, and diffusion means, including a spray nozzle 5, an air pump 7, a conduit 3 for admitting the fluid 2 into the spray nozzle 5, and control means 9 connected to the air pump 7. The spray nozzle 5, the reservoir 1 and the intake duct 3 are preferably made of a rigid injectable synthetic material (or, as a variant, machinable ), which is more inert and / or biocompatible relative to the liquid 2, chosen from a polyether, a polyacetal, a polyurethane, a nylon, a plastic material of the so-called delrin type, etc.

 The spray nozzle 5 comprises three coaxial pipes: a convergent pipe 5a, a constant section pipe 5c, and a divergent pipe 5b, the axis of these pipes defining a longitudinal direction of the spray nozzle. The spray nozzle moreover has a central bore opening onto the converging duct 5a, and receiving the fluid intake duct 3, and an eccentric bore 5d also opening onto the converging duct 5a, and receiving a portion. 6a of a supply duct 6 for the propellant gas flow generated by the air pump 7. The internal sections of the ducts 5a, 5b, 5c, 5d, 5e are preferably circular at all points. In

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 variant, square or rectangular sections are in accordance with the invention. The critical zone, the zone with the smallest internal section of the spray nozzle, corresponds to the internal space delimited by the duct 5c. It can be seen that solid deposits form and accumulate mainly in this zone and at the entrance to the divergent duct 5b.

 In operation, the spray nozzle is traversed by a propellant flow generated by the air pump 7, brought into the spray nozzle by the duct 6, and introduced into the converging duct 5a by an inlet orifice 10. The conduit 6 is formed of a conduit 6a integral with the spray nozzle 5 and integrated in a removable cartridge 30 described below, and of a conduit 6b fixed on the air pump 7.

The two conduits 6a, 6b are connected by any suitable means. The propellant flow generally flows substantially in the longitudinal direction of the spray nozzle, and defines a direction of flow from the converging duct 5a towards the divergent duct 5b to an orifice 11 at the outlet of the spray nozzle.

 The air pump 7 is preferably an electric pump regulated by frequency variation (principle known as Pulse Width Modulation) by the control means 9. Such a pump operates all or nothing, and delivers a propellant flow of constant flow per period of operation (10mn for example). A variation in the duty period / total period duty cycle makes it possible to vary the intensity of diffusion (and for example the olfactory intensity in the case of a perfume).

 The liquid 2 to be diffused is brought from the reservoir 1 into the spray nozzle via the liquid intake pipe 3, which passes through the central bore Se of the spray nozzle to open into a downstream portion of the convergent pipe 5a, to near the entrance to conduit 5c. The shape of the converging duct 5a, the arrangement of the intake duct 3 and the speed of flow of the propellant flow induce a depression near the outlet orifice 4 of the intake duct, which causes the suction of the liquid contained in the intake duct 3.

 The means for unblocking the spray nozzle 5 and the inlet conduit 3 comprise a unblocking rod 14 having an upstream projecting portion substantially of the same section as the smallest internal section (section of the conduit 5c) of the spray nozzle 5 , and a downstream portion supporting a closure cover 13. The rod is preferably made of stainless steel or of material

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distance séparant l'orifice d'entrée de ce conduit 5c et l'orifice de sortie 4 du conduit d'admission 3. Lorsque la lèvre périphérique est plaquée contre les parois internes du conduit 5b, l'extrémité amont de la tige vient ainsi en butée contre l'orifice de sortie 4 conduit d'admission, en vue de son obturation. La tige de débouchage 14 présente préférentiellement une extrémité amont 29 en matériau souple et étanche du type caoutchouc. rigid synthetic (in delrin for example). The closure cover 13 has a peripheral lip 28 of flexible synthetic material of the rubber type, which, at rest, forms an approximate angle of 45 with the axis of the unblocking rod, and, when it is pressed against the outlet orifice 11 of the spray nozzle, conforms to the internal walls of the divergent duct 5b so as to completely cover them and form, in the nonlimiting example illustrated, an angle of more than 100 with the axis of the rod. When the peripheral lip 28 is thus pressed against the internal walls of the divergent conduit Sb (see FIG. 3), the upstream projecting portion of the unblocking rod extends entirely upstream of the outlet orifice of the conduit 5c. The length of said projecting upstream portion of the unblocking rod 14 is chosen to be at least substantially equal to the sum of the length of the critical zone (length of the conduit of constant section 5c) and the

distance separating the inlet orifice from this duct 5c and the outlet orifice 4 from the inlet duct 3. When the peripheral lip is pressed against the internal walls of the duct 5b, the upstream end of the rod thus comes into abutment against the outlet orifice 4 intake duct, for its closure. The unblocking rod 14 preferably has an upstream end 29 made of flexible and waterproof material of the rubber type.

The spray nozzle 5, the reservoir 1, the intake duct 3, and part of the unblocking means comprising the unblocking rod 14, the shutter cover 13, the actuation shaft 12 and the return spring 22 (described in more detail below) are enclosed in a compact removable cartridge 30, adapted to be able to be installed in the tank quickly and easily. The cartridge 30 has a diffusion orifice 31 through which the cloud of microdroplets, which forms in the spray nozzle 5 and circulates in the cartridge 30, escapes and is ejected into the atmosphere. The location of this diffusion orifice relative to the outlet orifice 11 of the spray nozzle is indifferent with regard to the diffusion. The cartridge further comprises sealing means 32, 33 around the shaft 12, the control end 34 of which projects from the cartridge, and around the conduit 6a (connected to the conduit 6b when the cartridge 30 is installed in the device).

The use of such a cartridge has multiple advantages: - the spray nozzle being integral with the tank, the replacement of a used tank (empty for example) by a new tank

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er également le remplacement de la buse de pulvérisation. Cette opération est simple et rapide puisqu'un seul élément (la cartouche) est à changer, - lorsque la cartouche est hors du dispositif, le ressort de rappel 22 fixé à une extrémité sur le boîtier de la cartouche et à l'autre extrémité sur l'arbre 12, exerce une force sur l'arbre 12 maintenant la tige 14 (et le capot 13) en position de fermeture. Le liquide 2 à diffuser ne peut pas pénétrer dans la buse de pulvérisation 5, qui est ainsi protégée, - le réservoir 1 est avantageusement ouvert. Les moyens de diffusion sont adaptés pour permettre la formation et la diffusion dans l'atmosphère de microgouttelettes de diamètre suffisamment faible pour que lesdites gouttelettes ne soient pas perceptibles par les personnes présentes à proximité du dispositif de diffusion et qu'elles puissent être éjectées du dispositif-et suffisamment loin de celui-ci-par le flux propulseur s'échappant de la buse de pulvérisation 5, puis véhiculées par convexion naturelle à travers toute la pièce dans laquelle elles sont éjectées. Le réservoir étant ouvert, les gouttelettes de diamètre trop grand retombent par gravité dans le réservoir et ne sont pas inutilement diffusées.

Also replace the spray nozzle. This operation is simple and quick since only one element (the cartridge) needs to be changed, - when the cartridge is out of the device, the return spring 22 fixed at one end to the cartridge case and at the other end to the shaft 12 exerts a force on the shaft 12 holding the rod 14 (and the cover 13) in the closed position. The liquid 2 to be diffused cannot enter the spray nozzle 5, which is thus protected, - the reservoir 1 is advantageously open. The diffusion means are adapted to allow the formation and diffusion into the atmosphere of microdroplets of sufficiently small diameter so that said droplets are not perceptible by the people present near the diffusion device and that they can be ejected from the device. -and far enough from it by the propellant flow escaping from the spray nozzle 5, then conveyed by natural convection through the whole room in which they are ejected. The reservoir being open, the droplets of too large diameter fall by gravity into the reservoir and are not unnecessarily diffused.

 The means for actuating the unblocking rod 14 and the closure cover 13 include: a shaft 12 mounted in the device so as to be able to be moved in longitudinal translation along an axis at least substantially parallel to the axis of the unblocking rod 14, said shaft being extended by an arm 21 for rigid connection to the unblocking rod 14 and to the closure cover 13, a cam 18, driven in rotation about an axis orthogonal to the axis of the shaft 12 by an electric motor 15 controlled by the control means 9. To this end, the motor shaft 15 carries an endless screw 16 intended to cooperate with a gear wheel 17 carried by the cam 18, connecting means between the shaft 12 and the cam 18, able to transmit to the shaft, and to amplify, displacements in its longitudinal direction imposed by the variable contour of the rotating cam. Said connecting means comprise a flexible strip 20, on either side of which the cam 18 and the shaft 12 are in offset support so as to produce a lever arm between the cam and the shaft, and a spring of reminder 22, fixed on the shaft at one of its ends and on a fixed box of the

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dispositif de diffusion à l'autre de ses extrémités de façon xeruërune force de rappel

dans une direction parallèle à la direction longitudinale de l'arbre 12 tendant à plaquer l'arbre 12 contre la lamelle souple 20 et ladite lamelle contre la came 18.

diffusion device at the other of its ends in a xeruërune return force

in a direction parallel to the longitudinal direction of the shaft 12 tending to press the shaft 12 against the flexible strip 20 and said strip against the cam 18.

 The cam 18 has a contour adapted to make it possible to define at least three successive positions of the shaft 12 corresponding respectively, for the unblocking rod 14 and the shutter cover 13, to the diffusion, unclogging and closing positions. These three positions of the unblocking rod and the closure cover correspond to three positions A, B, C of the cam 18, identified by three magnets also referenced A, B, C of different inductances, embedded in housings provided in the cam 18. The magnets A, B, C cooperate with sensor means 19, of the Hall effect type for example, fixed in a fixed box of the diffusion device and connected to the control means 9. In an advantageous variant, the positions A, B, C are identified by reflecting pads detected by optical reading means, of the so-called optical fork type (infrared transmitter / receiver).

 The control means 9 comprise a central processing unit with microprocessor (s), memory means of the RAM type ("Random Acces Memory"), memory means of the ROM type ("Read Only Memory"), an internal clock of the “time-keeper” type, a power modulator such as a modulator by frequency variation called a PWM chopper (“Pulse Width Modulation”) for the regulation of the air pump 7, an analog / digital converter, means of control (pilot and input / output port) by the central processing unit of a human interface (not shown) comprising for example a control keyboard and a liquid crystal display screen, etc., autonomous means of partial supply to define a "standby" mode of the device in which only the central processing unit or a part thereof is supplied, software means in particular suitable for controlling the air pump 7 and the motor 15 according to the invention.

 The control means 9 are adapted to control the engine 15 and the air pump 7 according to a unblocking cycle comprising the following chronological steps: - verification of the position of the cam 18 by analysis of the signal emitted by the sensor means 19;

<Desc / Clms Page number 18>

 in the absence of a signal (no magnet facing the sensor), or in the presence of a signal other than that representative of the detection of the magnet A, activation of the motor 15 so as to drive the cam 18 in rotation until the cam is in position A as detected by the sensor means (magnet A opposite the Hall effect sensor 19, reception of a corresponding signal by the control means); the unblocking rod 14 and the shutter cover 13 are then in the diffusion position (FIG. 2); - activation of the motor 15 so as to cause the cam 18 to rotate in a clockwise direction from position A to position C (FIG. 3) as detected by the sensor means 19, then up to position B (figure 4). The contour of the cam 18 is adapted so that the passage from position A to position C causes a sudden displacement of the unblocking rod from its diffusion position to its closed position. The presence of the return spring 22 amplifies this phenomenon, thereby improving the removal of solid deposits present in the conduit 5c by the unblocking rod 14. Concomitantly with the rotation of the cam between positions A, C and B, the means of control 9 activate the air pump 7 in order to assist in the removal of solid deposits, and this for a predetermined period of time, preferably 4 seconds, - while the cam 18 is in position B (unclogging position of the cover 13 and the rod 14, in which the cover closes the outlet orifice 11 of the spray nozzle and the end piece 29 of the rod is spaced from the outlet orifice 4 of the intake duct 3), activation of the air pump 7 for a predetermined period of time, preferably 6 seconds, in order to discharge to the tank 1, by means of the propellant, the fluid and the particles present in the intake duct (debris from removal of solid deposits or other impurities initially present in the tank and sucked into the intake tube during diffusion), - activation of the motor 15 so as to drive the cam in rotation from its position B to its position A, and thus place the rod unblocking 14 and the shutter cover 13 in the diffusion position, - activation of the air pump 7 according to a nominal diffusion regime. A complete unblocking cycle is therefore carried out by rotating the cam 360.

<Desc / Clms Page number 19>

 The device also comprises means 8 for detecting an accumulation of solid deposits in the spray nozzle, connected to the control means 9. The detection means comprise a pressure switch 8 arranged on a control line 24 connected to the supply line 6 of the propellant, and calibrated to a trigger threshold value. The pressure switch 8 has a first pole connected to ground, and a second pole connected both to a pulling resistor supplied by a constant voltage and to a logic input of the control means 9 by a cable 25. The information received by the control means 9 is of binary type: when the pressure in the control line 24 is less than the threshold value for triggering the pressure switch, the pressure switch is with open contact and the information received by the control means 9 takes the value 0 ; when the pressure in the conduit 24 is greater than the threshold value for triggering the pressure switch, the contact is established and the information received by the control means takes the value 1. The threshold value for triggering the pressure switch is chosen according to the characteristics of the air pump 7, of the desired nominal diffusion speed, of the characteristics of the spray nozzle 5 and of the fluid to be diffused, so as to characterize a clogged state of said nozzle. The threshold value for triggering the pressure switch corresponds for example to the pressure of the propellant gas in the duct 24 in nominal diffusion mode, increased by N% with N = 10 for example. Achieving such a pressure in nominal diffusion mode means that the spray nozzle is at least partially blocked.

 When they receive the value 1 from the pressure switch signifying that the inlet pressure of the spray nozzle 5 has exceeded the threshold value, the control means 9 trigger the execution of a cleaning cycle.

 The unblocking cycle can also be triggered automatically by the control means 9 every 24 hours, and / or after a period of 5 hours of non-use of the spray nozzle 5. To this end, the control means are associated to a counter, mechanical or software, which, when the nozzle is not used to spray the fluid 2, increments for example every minute. After each incrementation, the current value of the counter is compared with a reference value, in example 300, stored in the storage means of the control means, and corresponding to the predetermined period of non-use chosen. When the two values are identical (or when the current value of the counter

<Desc / Clms Page number 20>

est supérieure a la valeur ce reference), les moyens de conTiDieucCumcnent un cycle ae débouchage et initialisent à zéro le compteur. Le compteur est interrompu à chaque utilisation de la buse de pulvérisation, durant toute la période d'utilisation, et remis à zéro en fin de période d'utilisation.

is greater than the value of this reference), the means of conTiDieucCumcnent a cycle with uncorking and initialize the counter to zero. The counter is interrupted each time the spray nozzle is used, throughout the period of use, and reset to zero at the end of the period of use.

 The unblocking cycle can also be triggered on command of a user, by means of a human interface (not shown) connected to the control means 9 by any suitable means: USB port in the case of an interface box fixed on the broadcasting device, infrared transmission and reception means in the case of an infrared remote control, modem and connection to the Internet network in the case of a remote centralizing computer, intended to control a plurality of broadcasting devices ...

 The device preferably comprises a plurality of reservoirs or cartridges (not shown). Propellant flow supply lines, provided with solenoid valves, are arranged between the air pump and each of the spray nozzles. The control means are suitable for controlling the opening of the solenoid valve supplying a propellant flow to the spray nozzle of a given cartridge, on reception of a signal representative of a selection of said cartridge, emitted by the control means. user (human interface). The control means are also advantageously adapted for: - controlling the closing of the solenoid valve supplying in propellant flow the spray nozzle of a first cartridge initially in operation, following the reception of a signal indicative of an accumulation of deposits solids in said nozzle despite the consecutive execution of a predetermined number (4 for example) of unclogging cycles, - select a second cartridge, check the clogged state or not of its spray nozzle, and order the opening of the solenoid valve supplying propellant flow to said second nozzle if the latter is not blocked, send a signal representative of an operating error occurred on the first cartridge intended for the human interface, - inhibit the air pump if the device does not include any other cartridge or that all the cartridges present are out of service (empty tank, blocked nozzle ...), and emit a signal device out of service.

<Desc / Clms Page number 21>

 The human interface advantageously comprises an on / off switch for controlling the device, connected to an input of the so-called external interruption type, denoted IT, of the central processing unit of the control means. On an output of said central processing unit is connected a relay or a power transistor of the so-called MOSFET type, capable of delivering a nominal operating power from a low power signal. This relay supplies all the electronic and electrical circuits of the diffuser.

 When the on / off contactor is pressed by the user in order to switch on the diffusion device (command to switch on the device), the central processing unit executes a start-up program stored at an address associated with the IT. According to this start-up program, the central processing unit activates the relay, which energizes the entire broadcasting device; the central processing unit then stores, as the address associated with the IT, that of a shutdown program; it then performs unblocking cycles for the spray nozzles for which it receives the value 1 ("nozzle blocked") from the associated pressure switch.

 When the on / off switch is pressed by the user in order to stop the broadcasting device (command to switch off the device), the central unit executes the stop program, the address of which is associated with the IT. According to this stop program, the central unit activates the motor (s) 15 in order to place each unclogging rod 14 in the closed position; the relay or MOSFET then de-energizes the entire broadcasting device; the central unit stores the address of the start-up program as the address associated with the IT, then executes an instruction for switching to standby mode.

 It goes without saying that the invention can be the subject of numerous variants with respect to the embodiments previously described and represented in the figures.

 In particular, the shape of the cam can be adapted to successively define the positions of diffusion, uncorking and closing (the contour of the cam in this case has a bulge opposite the magnet B), and thus allow movement directly the unblocking rod and the shutter cover from the diffusion position to the unclogging position (without passing through the closed position).

<Desc / Clms Page number 22>

In this version of the invention, the motor is preferably rotary in both directions; and the unclogging cycle is reduced to the displacement of the rod and of the cover from the diffusion position to the unclogging position by rotation of the cam in a first direction, upon activation of the pump to evacuate the debris caused via the intake duct, then the displacement, by rotation of the cam in the opposite direction, of the rod and of the cover from the unclogging position to the diffusion position.

 Any other embodiment of the actuation means, capable of allowing the realization of one of the unclogging cycles described above, and in particular to define the three positions of the unblocking rod and of the shutter cover, is in accordance with l 'invention. By way of example, it is possible to use means with electromagnets, distributed along the stroke of a shaft extending and supporting the unblocking rod and the shutter cover.

 Furthermore, the invention applies to other types of spray nozzle, and in particular to nozzles formed by a convergent duct extended by a duct of constant section opening directly to the outside (the outside designating either the exterior of the device is the interior of the cartridge containing the nozzle, etc.), or else to the nozzles composed of a conduit of constant section extended by a divergent conduit opening directly onto the exterior.

 On the other hand, the air pump can be regulated in power by variation of the supply current (intensity and / or voltage). Such a pump delivers a variable flow rate, chosen as a function of the desired intensity of diffusion. Each delivered flow corresponds to a normal operating pressure prevailing in line 6 when the spray nozzle is not blocked, and a threshold pressure reflecting a blocked state of the chosen spray nozzle equal to the normal operating pressure increased by 10 % for example. In this variant, the detection means advantageously comprise a pressure sensor in the conduit for supplying the propellant flow.

When the value of the pressure at the inlet of the spray nozzle, as detected by the sensor and transmitted to the control means, is greater than the threshold value corresponding to the flow rate delivered by the pump at the time of measurement, the spray nozzle is considered to be blocked.

 The threshold values are stored in the memory means of the control means or calculated by said control means as a function of the

<Desc / Clms Page number 23>

 flow / pressure curve of the pump, stored in said storage means. As a variant, they are stored on an information medium (magnetic, optical, of the barcode type for example, etc.) carried by the removable cartridge; the information carrier is in this case associated with suitable reading means, carried by a fixed part of the broadcasting device and controlled by the control means.

Claims (21)

1 / -A device for diffusing a liquid into the atmosphere in the form of droplets, comprising:

 at least one tank (1) containing a liquid (2) to diffuse, for each tank, means for diffusing into the atmosphere the liquid contained in the tank, comprising a spray nozzle (5), means (7) for generation of a propellant gas flow passing longitudinally through said spray nozzle, and an inlet conduit (3) into said nozzle of the liquid contained in the reservoir, opening upstream or facing an additional zone (5c) small internal section of the spray nozzle, called the critical zone, - said diffusion means being able to allow the formation of droplets of the liquid coming from the reservoir, the device being characterized in that it comprises, for each spray nozzle, means for unblocking said spray nozzle comprising: * a unblocking rod (14) adapted to be able to be displaced in longitudinal translation inside the spray nozzle (5) in order to tear off any deposits formed on the internal walls of the spray nozzle in the critical zone, * actuating means (18, 12, 15) capable of moving the unblocking rod between a position, called the diffusion position, in which the uncorking rod (14) extends outside the spray nozzle (5), at a distance from an outlet orifice (11) of said spray nozzle so as to allow diffusion, and a position, called unclogging position, in which the unclogging rod (14) extends inside the spray nozzle (5), through the critical zone (5c).  2 / -A device according to claim 1, characterized in that it comprises, for each spray nozzle and / or intake duct, means for unblocking the intake duct (3), comprising shutter means ( 13) of the outlet orifice (11) of the spray nozzle in order to allow to discharge towards the tank (1), by means of the propellant gas, the liquid and any particles present in said intake duct.  3 / -A device according to claim 2, characterized in that the sealing means comprise: <Desc / Clms Page number 25>  a shutter cover (13) of the outlet orifice (11) of the spray nozzle, means of arrangement (12, 18, 15) of the shutter cover able to move said shutter cover (13 ) between a diffusion position, at a distance from the outlet orifice (11) of the spray nozzle so as to allow diffusion, and a shutter position, in which the shutter cover is in abutment against the orifice (11) for exit from the spray nozzle with a view to closing it, 4 / -Device according to one of claims 1 to 3, characterized in that it comprises control means (9) capable of controlling, for each spray nozzle and / or intake duct, the means (7) generating propellant flow, the actuating means (15) of the control rod and, if necessary, the arrangement means (15) of the shutter cover.  5 / -A device according to claim 4, comprising at least one spray nozzle with lateral intake duct, characterized in that the control means are suitable for controlling the means for generating propellant flow, the means for actuating the unblocking rod and the means for arranging the closing hood so as to control the propellant flow generated and move the unblocking rod and the closing hood according to a unblocking cycle comprising the following chronological steps: - if necessary, positioning the unblocking rod and the closure cap in the diffusion position, - displacement of the unblocking rod from its diffusion position to its unclogging position,

 - displacement of the unblocking rod from its unclogging position to its diffusion position, - displacement of the closure hood from its diffusion position to its closure position, generation of a propellant flow during a lapse of time of predetermined time, - if necessary, displacement of the shutter cover from its shutter position to its diffusion position, and generation of a propellant flow according to a nominal diffusion regime. <Desc / Clms Page number 26>  6 / -Device according to claim C, ~ comprising at least one spray nozzle (5) with axial intake duct, characterized in that the closure cover (13) is carried by a downstream end of the unblocking rod (14) so that there is a common position of the unblocking rod and the closure cap, called the diffusion position, in which the unblocking rod and the closure cap are spaced from the orifice outlet of the spray nozzle so as to allow diffusion, and a common position of the unblocking rod and the shutter cover, called the unclogging position, in which the shutter cover (13) is in abutment against the outlet orifice (11) of the spray nozzle for its closure and the unblocking rod (14) extends inside the spray nozzle (5), through the critical zone (5c), and has an upstream end (29) remote from an outlet orifice (4) of the conduit inlet, the means for actuating the unblocking rod serving as means for arranging the shutter cover.  7 / -A device according to claims 4 and 6, characterized in that the control means (9) are adapted to control the means (7) for generating propellant flow and the actuation means (15) so as to control the propellant flow generated and move the unblocking rod (14) and the shutter cover (13) according to a unclogging cycle comprising the following chronological steps: - if necessary, positioning of the unclogging rod and the shutter cover in diffusion position, - displacement of the unblocking rod and of the shutter from the diffusion position to the unclogging position, - generation of a propellant flow for a predetermined period of time, - displacement, if necessary of the unblocking rod and of the closure cover from the unclogging position to the diffusion position, and generation of a propellant flow according to a nominal diffusion regime.  8 / -Device according to one of claims 1 to 7, comprising at least one spray nozzle with axial inlet duct, characterized in that the unblocking rod has an upstream end (29) adapted to be able to close a orifice outlet (4) of the intake duct (3), and in that the actuation means are adapted to be able to move said unblocking rod between its position <Desc / Clms Page number 27>  diffusion and an extreme upstream position (29), called the closed position, in which the upstream end of the unblocking rod abuts against the outlet orifice (4) of the intake duct with a view to closing it.  9 / -A device according to claims 6 and 8, characterized in that the closure cover comprises a peripheral lip (28) flexible, capable of deforming elastically to allow closure of the outlet orifice (11) of the nozzle spraying in the unclogging position and authorizing an additional displacement of the unclogging rod (14) to its closed position by crushing the peripheral lip (28) against the outlet orifice of the spray nozzle.  10 / -Device according to one of claims 5 or 7, characterized in that the control means (9) are adapted to periodically trigger, automatically, the execution of a cleaning cycle for each spray nozzle and / or intake duct.  11 / -A device according to one of claims 5,7 or 10, characterized in that, for each spray nozzle and / or intake duct, the control means (9) are adapted to trigger, automatically, the execution of a unclogging cycle after a predetermined period of non-use of said spray nozzle and / or of said intake duct.  12 / -A device according to one of claims 5,7, 10 or 11, characterized in that, for each spray nozzle and / or intake duct, the control means (9) are adapted to trigger the execution of a unblocking cycle on reception of a corresponding signal transmitted by means of communication of information to the control means by a user, called user control means.  13 / -A device according to one of claims 5,7, or 10 to 12, characterized in that it comprises, for each spray nozzle, detection means (8) of an accumulation of solid deposits on the walls internal of said spray nozzle, capable of transmitting to the control means (9) a signal indicative of an accumulation of solid deposits in said spray nozzle (5), on reception of which the control means are adapted to trigger a cycle of uncorking of said spray nozzle. <Desc / Clms Page number 28>  14 / -A device according to claim 13, the flow generation means of which comprise an air pump (7) controlled in power by the control means (9), characterized in that, for each spray nozzle, the means for detection comprise pressure sensor means (8) capable of emitting, to the control means, a signal indicative of an accumulation of solid deposits if the pressure at the inlet of the spray nozzle is greater than a predetermined threshold value characteristic of 'an accumulation of solid deposits in said spray nozzle.  15 / -A device according to one of claims 13 or 14, the flow generation means of which comprise an electric air pump controlled in power by the control means, characterized in that, for each spray nozzle, the means for detection comprise means for measuring the intensity of the supply current of the air pump, capable of emitting, intended for the control means, a signal indicative of an accumulation of solid deposits if the intensity measured is greater than a predetermined threshold value characteristic of an accumulation of solid deposits in said spray nozzle.  16 / -A device according to one of claims 13 to 15, characterized in that the control means (9) are adapted to inhibit the means (7) of generating propellant flow associated with a spray nozzle (5), and send, to information communication means to a user, called user information means, a signal representative of an operating error, if they receive a signal indicative of an accumulation of solid deposits in said nozzle spraying immediately after the execution of a predetermined number of immediately consecutive unclogging cycles.  17 / -Device according to one of claims 1 to 16 and according to one of claims 3 or 5, characterized in that the control means (9) are adapted to trigger the execution of a cleaning cycle for each spray nozzle (5) following a command to switch on the device.  18 / -A device according to one of claims 1 to 17 and according to claim 6, characterized in that, for each spray nozzle (5), the control means are adapted to activate the actuation means (15) of way to arrange <Desc / Clms Page number 29>  the unblocking rod (14) in the closed position following a command to power off the device.  19 / -Device according to one of claims 1 to 18, characterized in that it comprises one (s) spray nozzle (s) of injected synthetic material, manufactured (s) from an impression having undergone electrolytic polishing and / or a superfinish at least on a surface delimiting the critical zone.  20 / -Device according to one of claims 1 to 18, characterized in that it comprises one (of) spray nozzle (s) of machined spray (s), having undergone electrolytic polishing and / or at least superfinishing on internal walls facing the critical zone.  21 / -A device according to one of claims 1 to 20, characterized in that each spray nozzle has internal walls coated, at least opposite the critical zone, with a coating with a low coefficient of adhesion of the Teflon type .