TECHNICAL FIELD

The invention relates to an inhalation device with at least one liquid jet device.

In recent years, inhalation devices such as e-cigarettes have become popular as a replacement for conventional smoking articles. In this context, a certain amount of liquid has to be stored in the inhalation device, preferably in a replaceable cartridge and has to be delivered appropriately to a heater so as to form an aerosol.

PRIOR ART

US 2021/0008577 A1 discloses a spray device or inhaler that includes a nozzle unit and micro jets to generate droplets or liquid. A pressure valve is integrated between a syringe and the nozzle body that opens at a predetermined pressure and else remains close.

US 10,219,544 B2 describes an aerosol delivery device that includes ink jet spray devices to spray aerosol particles. A selector element i.e. a valve is disposed within a heating sub-chamber and a respective outlet port. The valve remains closed and opens in response to suction applied through the respective outlet port.

Further examples of the prior art can be seen in documents CN 205 831 081 U, US 2017/290369 A1, US 2019/321570 A1 and US 2017/265526 A1.

SUMMARY OF THE INVENTION In view of the above, there remains a need for an improved inhalation device, which can avoid undesired leakage of liquid when the inhalation device is not in use.

This is achieved by means of the inhalation device in accordance with claim 1, which has at least one liquid jet device having at least one nozzle to dispense liquid drops on demand in a mouthpiece, wherein the inhalation device further comprises a valve; wherein at least one nozzle is closable by the valve.

Indeed, the valve closing the nozzle can easily be integrated into the device and effectively impedes the liquid contained in the inhalation device to come out when this is not desired or necessary.

Preferred embodiments are described in the further claims.

As regards the liquid jet device, providing same as a MEMS (Micro-Electro-Mechanical System) has proven efficient, as such technology is well established for drop on demand technology .

According to a preferred aspect of the invention, the valve is a flap valve.

This allows to provide the inhalation device with a simple and reliable valve. Constructional simplicity also allows to increase reliability and to reduce production costs.

According to a preferred aspect of the invention, the valve is adapted to cover the nozzle.

Thus, the valve can efficiently prevent the leakage of liquid from the device in a simple way.

According to a preferred aspect of the invention, the valve is adapted to be opened by the pressure applied by the liquid drops ejected from at least one nozzle.

Due to this feature, the driving of the valve is simplified, and the valve is opened only when the inhalation device is in use. Thus, the valve can be driven precisely and reliably.

According to a preferred aspect of the invention, the valve is biased to a state closing the nozzle.

This allows the valve to maintain a stable position in a closed configuration. This reduces the risk of unexpected and undesired leakage of liquid when the valve is closed and, hence, when the inhalation device is not in use. This is also relevant when the inhalation device, when not in use, is accidentally moved by the user. Therefore, even when the device is subjected to undesired forces, the valve is maintained in a closed configuration.

According to a preferred aspect of the invention, the valve member extends essentially perpendicular to a longitudinal axis of the inhalation device.

Thus, the movement of the valve can be simplified and sufficiently quick to allow a prompt ejection of liquid when necessary .

BRIEF DESCRIPTION OF THE DRAWINGS

Hereinafter, the invention is further described with reference to the drawings, in which:

FIG. 1 shows a schematic view of an inhalation device in accordance with the invention in a first operating condition; FIG. 2 shows a schematic view of the inhalation device of Figure 1 in a second operating condition.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

As can be taken from Figures 1 and 2, the inhalation device 10 as described herein comprises a case 18 which is essentially elongated. For example, the case 18 can be of cylindrical shape extending along a longitudinal axis. The longitudinal axis of the case 18 defines the longitudinal axis of the inhalation device 10.

In addition, the inhalation device 10 comprises a mouthpiece 12 arranged at one end of the case 18. Further, the inhalation device 10 comprises charging contacts 14 arranged at the other end of the case 18.

Any aerosol delivered to the mouthpiece 12 is produced from liquid contained in a reservoir 16, which is essentially accommodated in that half of the case 18, which is closer to the mouthpiece 12.

The longitudinal axis of the case 18 corresponds to a longitudinal axis of the reservoir 16. The reservoir 16 can comprise a cartridge, preferably a replaceable cartridge.

In the present case, aerosol is produced by at least a liquid jet device 24 which is functionally and structurally arranged between the reservoir 16 and the mouthpiece 12. The liquid jet device 24 is configured to produce liquid drops on demand.

A supply tube 26 is connected between the reservoir 16 and the liquid jet device 24 to supply the liquid to be vaporized to the liquid jet device 24. The reservoir 16 comprises a filter 28 arranged directly downstream of the supply tube 26. For example, the filter 28 comprises a bung made of cotton. Preferably, the filter 28 is arranged close to the liquid jet device 24. More preferably, the filter 28 is arranged in contact with the liquid jet device 24.

The inhalation device 10 further comprises a printed circuit board or PCB 30 which is arranged in the case 18 and is connected to the liquid jet device 24.

Further, the inhalation device 10 comprises a rechargeable battery 32 which is connected to the printed circuit board 30 to provide power to the liquid jet device 24. The battery 32 is further connected to the charging contacts 14.

The liquid jet device 24 may comprise a micro heater or a resistor .

In a preferred embodiment of the invention, the liquid jet device 24 comprises a MEMS die. The MEMS die is connected with the printed circuit board 30. Preferably, the MEMS die is rigidly and directly connected to the printed circuit board 30.

The liquid jet device 24 comprises at least a nozzle to dispense the vaporized liquid in the mouthpiece 12.

In other embodiments which are not represented, the inhalation device 10 may comprise a plurality of liquid jet devices 24, each connected to the printed circuit board 30 and each comprising a respective nozzle.

According to the invention, the inhalation device 10 comprises a valve 40 associated to the nozzle, as can be seen in Figures 1 and 2. The valve 40 is configured to open and close the nozzle.

More in detail, the valve 40 switches between a first configuration (closed configuration, Figure 1), in which it covers the nozzle, impeding the leak of liquid therethrough, and a second configuration (opened configuration, Figure 2), in which it exposes the nozzle, allowing the passage of liquid.

Preferably, the valve 40 is a flap valve.

More in detail, the valve 40 comprises a flap or valve member 42 which is rotatably connected to the case 18 through a hinge 44.

Alternatively, a flap 42 may be rotatably connected to the mouthpiece 12 through the hinge 44.

When the valve 40 is in the first configuration, the flap 42 is near the nozzle. More in detail, when the valve 40 is in the first configuration, the flap 42 is in contact with the nozzle to close it and impede the leakage of liquid.

When the valve 40 is in the second configuration, the flap 42 is far from the nozzle so that it opens, and the liquid can be dispensed.

The flap 42 has a substantially flat shape. When the valve 40 is in the first configuration, the flap 42 extends essentially perpendicular to the longitudinal axis of the case 18.

When the inhalation device 10 is not in use, the valve 40 is in the first configuration. This avoids undesired leakage of liquid. When the inhalation device 10 is in use, the liquid jet device 24 dispenses liquid in the form of drops of vaporized liquid. In this regard, the valve 40 is configured to be opened by the pressure of the dispensed liquid.

In other words, the pressure of the liquid being dispensed by the liquid jet device 24 causes the switching of the valve 40 from the first configuration to the second configuration.

Alternatively, the valve 40 is configured to be opened by negative pressure generated by the user during inhalation.

According to an embodiment of the present invention, the valve 40 is configured to be opened by both the pressure of the dispensed liquid and the negative pressure generated by the user during inhalation.

When the use of the inhalation device 10 is stopped, the fall of the liquid pressure determines the passage of the valve 40 from the second configuration to the first configuration.

Preferably, the valve 40 is biased in the first configuration when the inhalation device is not in use.

In this regard, elastic means may be active on the valve 40. More in detail, the elastic means may be active on the flap 42. For example, the elastic means may comprise a helical spring generating an elastic force on the flap 42.

Although detailed embodiments have been described, these only serve to provide a better understanding of the invention defined by the independent claims and are not to be seen as limiting .