The invention relates to a method for dispensing an active substance, in which method the active substance is delivered bound to carrier particles to indoor or respiratory air. The invention also relates to a dispenser for dispensing an active substance to indoor or respiratory air.

Several different methods for dispensing an active substance together with an aerosol to indoor or respiratory air are known in the prior art. For example, metered aerosols that use a valved holding chamber or a powder dispenser are used for the treatment of pulmonary diseases. It is often necessary, however, to use a respirator mask or the dispenser must be brought close to the face for the administration of the active substance. An issue with the solutions of the prior art in which the active substance is dispensed freely to indoor air is the unreliability of the metering of the active substance. It is not possible to dispense the active substance to the indoor air in such a manner that the dose that ends up in the lungs is controllable in a reliable manner.

An object of the invention is to provide a new method for dispensing an active substance to indoor or respiratory air. The characteristic features of this invention are indicated in the attached patent claim 1. A further object of the invention is to provide a new dispenser for dispensing an active substance to indoor or respiratory air. The characteristic features of this invention are indicated in the attached patent claim 9.

In the method for dispensing an active substance according to the invention, the active substance is delivered bound to carrier particles to the indoor or respiratory air. In the method, a mixture of carrier particles and a liquid carrier substance is formed, which is sprayed into a process chamber onto a hot surface, where the liquid carrier substance is vaporized in order to release the carrier particles into the air of the process chamber, inlet air is fed at a selected temperature into the process chamber in order to cool the free carrier particles to a desired temperature and so as to form a flow of carrier air from an inlet port to an outlet port of the process chamber, an active substance is sprayed into the process chamber, the active substance is brought into collision with the free carrier particles so as to bind the active substance to the carrier particles, and the mixture of active substance bound to carrier particles is conducted into the indoor or respiratory air. The active substance can thereby be reliably dispensed to indoor or respiratory air in precise concentrations .

A flow of carrier air is understood in this case to be a flow of air inside the process chamber from the inlet port to the outlet port. The flow rate of the flow of carrier air can be 10 - 300 1/s, advantageously 30 - 100 1/s.

Both the active substance and the carrier particle can respectively be in a liquid state. Alternatively, both the active substance and the carrier particle can respectively be a solid substance, a mixture of which is formed with a liquid. The mixture must be pumpable and sprayable for a selected period of time. The mixture can also be precipitable, as long as it remains in a pumpable form for a while.

Advantageously, the carrier substance is water and a solution or dispersion is formed from the carrier particles and water, which is sprayed into the process chamber onto the hot surface. The carrier substance is thus readily available and inexpensive. The carrier particles do not have to be water-soluble; instead, a sprayable dispersion can be formed from the carrier particles and water.

Advantageously, the active substance is mixed with water so as to form a solution or dispersion, which is sprayed into the process chamber. The active substance can thus be sprayed homogeneously into the process chamber, whereby it is possible to regulate a concentration of the active substance in the indoor or respiratory air in a reliable manner.

Advantageously, activated carbon is used as the carrier particle. The carrier particles are thus readily available and inexpensive. If activated carbon is used, it is first pulverized into a fine dust. The grain size of the dust is reflected by the fact that the activated carbon that has been pulverized into dust continues to float in the indoor air for a long time. The activated carbon can then be mixed with water in order to form a dispersion. The thus formed dispersion of activated carbon and water can remain evenly mixed for over a week.

The mixture of carrier particles and liquid carrier substance can be periodically sprayed into the process chamber, advantageously 0.1-1 ml/h, and 5-60 pl, advantageously 10-20 pl, at a time. The delivery of the active substance to the indoor or respiratory air can thus be regulated reliably. Thanks to the employed method, the consumption of the mixture of carrier particles and liquid carrier substance is very low.

The mixture of carrier particles and liquid carrier substance can be periodically sprayed into the process chamber in such manner that 5-50, advantageously 10-20, spraying events occur in each cycle. The duration of a single spraying event can be 0.5-20 ms, advantageously 1-10 ms. An interval between spraying events can be 5-60 s, advantageously 10-25 s. A longer interval can be set between cycles. By means of the setting of the spraying cycles, it is possible to regulate the concentration of the active substance that ends up in the indoor or respiratory air with precision.

The spraying of the active substance into the process chamber can be synchronized so that the active substance is sprayed into the process chamber after a delay following the spraying of the mixture of carrier particles and liquid carrier substance. The delay can be 0.5-5 s, advantageously 1-2 s. This gives the carrier particles released on the hot surface time to cool down sufficiently before colliding with the active substance and gives the flow of carrier air time to transport the carrier particles from the hot surface to the site where the active substance is sprayed.

Advantageously, the active substance has a biological or chemical effect on humans or animals or both. The method according to the invention can thus be used to dispense medicinal substances. For example, experiments have been carried out using eucalyptus as the active substance, which has healthful effects on the human organism.

Advantageously, the flow of carrier air forms a vortex flow in the process chamber. The carrier particles and the active substance can thereby be mixed effectively in the process chamber in order to increase the probability of collisions of the carrier particles and the active substance.

The active substance can be sprayed into the process chamber away from the hot surface, advantageously at a distance of 20 - 80 cm, more advantageously 25 - 50 cm, away from the hot surface. The active substance is thus not heated; rather, the active substance is brought into collision with the cooled carrier particles.

A dispenser for dispensing an active substance bound to carrier particles to indoor or respiratory air according to the invention includes a process chamber, a first dispensing container for dispensing a mixture of carrier particles and a liquid carrier substance, a second dispensing container for dispensing an active substance, a first feed tube for feeding the mixture of carrier particles and liquid carrier substance from the first dispensing container into the process chamber, a second feed tube for feeding the active substance from the second dispensing container into the process chamber, a first spraying unit comprising a nozzle for spraying the mixture of carrier particles and liquid carrier substance from the first dispensing container into the process chamber via the first feed tube, a second spraying unit comprising a nozzle for spraying the active substance from the second dispensing container into the process chamber via the second feed tube, a hot surface in the process chamber for vaporizing the mixture of carrier particles and liquid carrier substance, an outlet port for conducting the mixture of active substance bound to carrier particles into the indoor or respiratory air, an inlet air unit comprising a motor and a heater for forming a flow of carrier air into the process chamber at a selected temperature, the inlet air unit being connected to the process chamber by an inlet port, and the flow of carrier air being formed from the inlet port to the outlet port, wherein, in the dispenser, the nozzle of the first spraying unit is directed towards the hot surface in the process chamber in order to spray the mixture of carrier particles and liquid carrier substance onto the hot surface, the nozzle of the first spraying unit is closer to the hot surface and to the inlet port than the nozzle of the second spraying unit, and the nozzle of the second spraying unit is closer to the outlet port than the nozzle of the first spraying unit. The dispenser can thus be used for a reliable dispensing of an active substance to indoor or respiratory air in precise concentrations.

The distance of the nozzle of the first spraying unit from the hot surface can be 1 - 15 cm, advantageously 5 - 10 cm, and the distance of the nozzle of the second spraying unit from the hot surface can be 20 - 100 cm, advantageously 25 - 60 cm. It is thereby possible for the mixture of carrier particles and liquid carrier substance to be sprayed directly onto the hot surface for vaporization and for the active substance to be sprayed away from the hot surface and brought into collision with the cooled carrier particles, whereby the active substance is not heated .

The distance between the nozzle of the first spraying unit and the nozzle of the second spraying unit can be 10-100 cm, advantageously 15-40 cm. This gives the carrier particles that are released on the hot surface time to cool down sufficiently on their way to the second spraying unit.

Advantageously, the carrier particle is activated carbon. The carrier particles are thus readily available and inexpensive.

Advantageously, the inlet port is arranged tangentially to the process chamber in order to form a vortex flow in the process chamber. The binding of the active substance to the carrier particles is thus rendered more effective.

Advantageously, the inlet port and the outlet port are respectively located at opposite ends of the process chamber, and the hot surface is located closer to the inlet port than to the outlet port, so that the inlet air unit forms a flow of carrier air from the hot surface towards the outlet port. It is thereby possible for the carrier particles to be transported from the hot surface to the outlet port.

Advantageously, the process chamber comprises a reaction-temperature temperature sensor. It is thus possible to monitor the temperature in the process chamber. More specifically, it is possible to monitor the temperature at the site where the active substance is brought into collision with the carrier particles so that conditions for forming the mixture of active substance bound to carrier particles can be suitably adapted.

Advantageously, the inlet air unit comprises an inlet-air-tem- perature temperature sensor. It is thus possible to monitor the temperature of the inlet air and thereby to regulate the heating of the inlet air, whereby advantageous conditions for the active substance are achieved.

Advantageously, the operating temperature of the hot surface is 70-300 °C. It is thereby possible for the carrier substance to be vaporized efficiently in the process chamber without heating the process chamber needlessly.

Advantageously, the inlet air unit is configured to heat the inlet air of the process chamber to a temperature of 10-60 °C. It is thereby possible for the carrier particles to be cooled to a desired temperature after the vaporization of the carrier substance .

A positive pressure of 5-150 Pa, advantageously 30-100 Pa, vis- a-vis the air pressure of the surrounding indoor space can be provided in the process chamber by means of the blowing of the inlet air unit and by a dimensioning of the outlet port relative to the dimensioning of the inlet port. It is thereby possible to optimize the binding of the active substance to the carrier particles .

The power of the motor of the inlet air unit can be 10 - 500 W, advantageously 20 - 100 W. It is thereby possible to form a sufficient air flow inside the dispenser so that an air volume of the entire indoor space can theoretically be circulated through the dispenser and treated in a selected period of time, for example 10 minutes.

Inside the dispenser, the flow rate of the flow of carrier air generated by the inlet air unit in an operating state can be 10 - 300 1/s, advantageously 30 - 100 1/s. An entire air volume of an indoor space of a selected size, for example an office space, can thereby be treated within a selected period of time, for example 10 minutes.

The nozzle of the first spraying unit and/or the nozzle of the second spraying unit can be a piezo nozzle, which can advantageously be opened with a 1 ms control pulse. It is thereby possible to control spraying with precision by means of rapid spraying cycles. Advantageously, the operation of the nozzle of the first spraying unit and the operation of the nozzle of the second spraying unit are timed with respect to one another with a precision of 1 ms through the use of piezo nozzles for the spraying.

Advantageously, the dispenser includes a control unit, which is configured to control at least the spraying of the mixture of carrier particles and liquid carrier substance into the process chamber, the spraying of the active substance into the process chamber, the heating of the hot surface, the heater and the motor of the inlet air unit. The active substance can thereby be dispensed to the indoor or respiratory air at a desired concentration fully automatically.

The invention is illustrated in the following in detail with reference to the attached drawings illustrating embodiments of the invention, wherein

Figures la-lc illustrate steps of the method according to the invention,

Figure 2 schematically illustrates a cross-section of a dispenser according to the invention in a side view,

Figure 3a illustrates a cross-section of a further embodiment of a dispenser according to the invention in a side view,

Figure 3b illustrates an embodiment of a dispensing unit of a dispenser according to the invention,

Figure 4 schematically illustrates an embodiment of a dispenser according to the invention in a top view,

Figure 5 illustrates an embodiment for the use of a dispenser according to the invention.

Figures la-lc illustrate steps of the method according to the invention .

In Figure la, in a first step of the method, a mixture 200 of carrier particles 201 and a liquid carrier substance is formed, which is sprayed from a first spraying unit 131 in a process chamber 60 onto a hot surface 50. The mixture 200 of carrier particles 201 and liquid carrier substance vaporizes on the hot surface 50, whereby free carrier particles 201 are formed in the air of the process chamber 60. The free carrier particles 201 diffuse away from the hot surface 50, the diffusion towards an outlet port 110 being further promoted by means of a flow of carrier air provided in the process chamber 60. The flow of carrier air also cools the free carrier particles 201 that are formed on the hot surface 50, as certain active substances 202 are very sensitive to temperature.

In Figure lb, in a second step of the method, an active substance 202 is sprayed into the process chamber 60 from a second spraying unit 132. The second spraying unit 132 is further away from the hot surface 50 than the first spraying unit 131. In particular, the nozzle of the second spraying unit 132 is further away from the hot surface 50 than the nozzle of the first spraying unit 131.

In Figure 1c, in a third step of the method, the active substance 202 is brought into collision with the free carrier particles 201 in the process chamber 60, whereby the active substance 202 adheres to the carrier particles 201. The active substances 202 bound to the carrier particles 201 are transported in the form of a mixture 204 of active substance 202 bound to carrier particles 201 by the flow of carrier air to the outlet port 110 of the process chamber 60. The mixture 204 of active substance 202 bound to carrier particles 201 is conducted from the outlet port 110 either freely into a room or into a respirator mask to the indoor or respiratory air.

It is possible to use a dispenser 8 through which indoor air is circulated in the method according to the invention. Figure 2 illustrates an embodiment of a dispenser 8 according to the invention. Figure 3a illustrates a further embodiment of a dispenser 8 according to the invention. Figure 3b illustrates an embodiment of a dispensing unit 100 of the dispenser 8 in greater detail. A mixture 200 of carrier particles 201 and a liquid carrier substance is placed in a first dispensing container 91. The mixture 200 of carrier particles 201 and liquid carrier substance can be, for example, a mixture of activated carbon and water. An active substance 202 is placed in a second dispensing container 92. A constant pressure is established in the first dispensing container 91 and in the second dispensing container 92 by means of an air pump 101 and a pressure regulator 102, which are connected to the first dispensing container 91 and to the second dispensing container 92 via a manifold 105. The mixture 200 of carrier particles 201 and liquid carrier substance flows at a constant pressure from the first dispensing container 91 along a first feed tube 81 to a flow regulator 107 and further onwards via a high-pressure pump 108 to a first spraying unit 131. The active substance 202 flows at a constant pressure from the second dispensing container 92 along a second feed tube 82 to a flow regulator 107 and further onwards via a high-pressure pump 108 to a second spraying unit 132. The first spraying unit 131 and/or the second spraying unit 132 can comprise one or more nozzles. The first spraying unit 131 and the second spraying unit 132 can comprise, for example, piezo nozzles. The pressure is raised by means of the high-pressure pumps 108 so as to be suitable for piezo nozzles.

A process chamber 60 comprises a hot surface 50, which is heated by a power heater to 70-300 °C before the mixture 200 of carrier particles 201 and liquid carrier substance is sprayed onto the hot surface 50 in the process chamber 60. The mixture 200 of carrier particles 201 and liquid carrier substance sprayed from the first spraying unit 131 into the process chamber 60 vaporizes on the hot surface 50, whereby carrier particles 201 are released into the process chamber 60. The free carrier particles 201 are cooled to a desired temperature by inlet air entering the process chamber 60 from an inlet port 15. The regulation of the temperature is essential in light of the temperature sensitivity of the active substances 202 that are to be sprayed into the process chamber 60.

Arranged in the inlet port 15 of the dispenser 8 is an inlet air unit 10, the motor 12 of which sucks air from the indoor air outside the dispenser 8 into the dispenser 8 through an air filter 11 and blows the air into the process chamber 60. By means of the inlet air unit 10, a flow of carrier air of 10- 300 1/s, advantageously 30-100 1/s, is created in the process chamber 60 from the inlet port 15 to the outlet port 110. The direction of the air flow inside the dispenser 8 is thus upwards from the bottom in Figures 2 and 3a. The flow of carrier air transports the free carrier particles 201 from the hot surface 50 near the inlet port 15 into the upper part of the process chamber 60 towards the outlet port 110. The air passes through a heater 13 in the inlet air unit 10 before entering the process chamber 60. It is thereby possible for the inlet air to be purified and heated to the right temperature, for example 10- 60 °C, as certain active substances 202 are very sensitive to temperature. The heater 13 of the inlet air unit 10 and the hot surface 50 of the process chamber 60 together influence the temperature of the air inside the process chamber 60. In light of the temperature dependence of the active substance 202, the air temperature is controlled in particular in the upper part of the process chamber 60, where the noz zle/noz zles of the second spraying unit 132 are located. Advantageously, the temperature of the air leaving the outlet port 110 is adjusted to 36-42 °C. Advantageously, at least the temperature of the inlet air of the process chamber is monitored by a temperature sensor 71 and the reaction temperature of the process chamber is monitored by a temperature sensor 70. In addition, the blowing of the inlet air unit 10 causes a positive pressure in the process chamber 60 vis-a-vis the surrounding indoor air, which improves the binding of the active substances 202 to the carrier particles 201. The heating of the hot surface 50 and the narrowing of the outlet port 110 vis-a-vis the inlet port 15 also raise the pressure in the process chamber 60. In an operating state, the pressure in the process chamber 60 of the dispenser 8 is typically 5-150 Pa, advantageously 30-100 Pa, relative to the air pressure of the surrounding indoor air.

The embodiment of a dispenser 8 according to the invention shown in Figure 4 in a top view illustrates the geometry of the inlet air unit 15 and process chamber 60. The inlet port 15 is joined tangentially to the outer edge of the process chamber 60. The blowing of the inlet air thus brings about a rotation and mixing of the air mass in the process chamber 60.

The active substance 202 is sprayed into the process chamber 60 from the second spraying unit 132, which is located in an upper part of the process chamber 60 further away from the hot surface 50 in the direction of air flow than the first spraying unit. The distance between the nozzle of the first spraying unit 131 and the nozzle of the second spraying unit 132 can be, for example, approximately 25 cm or 35 cm. The active substance 202 can be mixed with, for example, water, so that it is easy to spray the active substance 202 into the process chamber 60. The active substance 202 is sprayed into the cooled carrier particles 201, whereby the active substance 202 binds to the carrier particles 201. The mixture 204 of active substance 202 bound to carrier particles 201 is conducted together with the flow of carrier air to the outlet port 110 of the dispenser 8 and from there to a desired target such as freely into indoor air or into a respirator mask.

When the dispenser 8 is in operation, the motor 12 and the heater 13 of the inlet air unit 10 are always on so that the indoor air of the space of application is circulated continuously through the dispenser 8. For example, the air flow can be dimensioned so that a volume of air corresponding to the space of application passes through the dispenser 8 in approximately 10 minutes. Therefore, in a space of application of, for example, 50 m ³ , the flow rate is set to 50 m ³ / 10 min, i.e. 83 1/s. If the diameter of the inlet port 15 is, for example, 100 mm, then the air flow rate into the process chamber 60 is 2.64 m/s . If the distance between the nozzle of the first spraying unit 131 and the nozzle of the second spraying unit 132 is, for example, 25 cm, the time required for the air to travel between the nozzle of the first spraying unit 131 and the nozzle of the second spraying unit 132 is at a minimum 95 ms. However, the diameter of the process chamber 60 in this embodiment, 300 mm here, is larger than the diameter of the inlet port 15 so that the air flow rate slows down at the process chamber 60. In addition, due to the geometry of the inlet air unit 15 and the process chamber 60, the air mass swirls in the process chamber 60. The aforementioned required time is thus slightly longer; the nozzles of the dispenser 8, however, have to operate with a precision of 1 ms due to the order of magnitude of the flight time of the carrier particles 201.

The nozzle of the first spraying unit 131 and the nozzle of the second spraying unit 132 in this embodiment are thus fastacting piezo nozzles, which are controlled with a 12 V DC voltage pulse and a 1 A current and which open at a minimum with a pulse of 1 ms. In addition, the heater 13 of the inlet air unit 10 in this embodiment has a power of 1200 W and the motor 12 has a power of 30 W. The hot surface 50 of the process chamber 60 is heated with a power of 300 W. The high-pressure pumps 108 are used with a 12 V DC voltage and a current of 6 A. The active substance 202 is sprayed into the process chamber 60 in very small quantities. The amount of active substance 202 to be sprayed can be in the order of 0.3 ml/h.

The dispenser 8 also includes a control unit 120 for controlling the spraying of the mixture 200 of carrier particles 201 and liquid carrier substance into the process chamber 60, the spraying of the active substance 202 into the process chamber 60, the heating of the hot surface 50, the heater 13 and the motor 12 of the inlet air unit 15. The connections of the dispenser 8 additionally include a power supply, which is not illustrated in the figures.

A floor or side of the process chamber 60 comprises a maintenance hatch 40 for maintenance.

Figure 5 illustrates an embodiment for the use of a dispenser 8 according to the invention. The dispenser 8 can be arranged, for example, in an office space in order to dispense an active substance 202, in the form of a mixture 204 of active substance 202 bound to carrier particles 201, to the indoor air. The active substance 202 can be, for example, a medicinal substance that is administered to people's lungs via indoor air.