FR3107197A1 - Rotating Disc Nebulizer for Inhalation - Google Patents

Abstract

Rotating disc nebulizer for aerosol inhalation. The present invention relates to a miniature nebulizer having certain improvements making it capable of diffusing into the mouth or into the nose a defined quantity of aerosols produced by an object rotating at high speed placed in a body provided with a slot. This device is particularly suitable for dispensing drugs to be taken in aerosol form.

Description

Rotating disk nebulizer for inhalation

When you want to obtain an aerosol, you most often use a nozzle nebulizer. In this type of device, a liquid is pressurized by a gas in a box provided with an orifice. When this orifice is opened, the liquid disperses through it and forms an aerosol whose properties depend on several factors such as the pressure in the case, the nature of the gas putting the liquid under pressure, the dimensions and the shape. of the orifice. These devices have a number of drawbacks, in particular there is a significant risk of clogging at the nozzle and it is very difficult to control the diameter of the drops which also have a high particle size dispersion.

The aim of the present invention is to propose a new nebulizer intended for the inhalation by the mouth or the nose of aerosols. This nebulizer is based on the technology of rotating objects to which it brings a certain number of improvements.

A rotating object nebulizer mainly consists of an object (disc, bowl, …) rotated by a high-speed motor and supplied with liquid in its center or near its center. Depending on the case , the feed can be made by gravity or by a pump.

It is known that when liquid is sent to the center of a rotating object or near its center, the liquid spreads over the object and, in certain configurations of rotational speed and flow rate, disperses near the center of the object. edge of the object into filaments which themselves resolve into droplets. When the droplets formed are small, for example with diameters less than 100 micrometers, they are little influenced by gravity, but are sensitive to the wind and in its absence practically propagate in the plane of rotation of the object.

It is known that the granulometry of the aerosols is a very important factor when one wants to inhale drugs, because according to the size of the drop this one will stop in the nose or the mouth, in the throat or penetrate in the lungs being able to come out of it or not.

It is known that the size of the droplets generated by a rotating object nebulizer can range from a few micrometers to a few hundred micrometers by adapting the flow rate, the rotational speed of the object, the size of the object and that the particle size dispersion can be very weak when certain conditions related to the mechanics of fluids are met or by printing vibrations for example.

It is known that the droplets generated by the rotating object nebulizer have an initial speed close to the speed of rotation of the object and that, continuously slowed down by air resistance, they stop at a distance from the object called stopping distance that we know how to calculate from the laws of aerodynamics,

All these properties give the rotating disc nebulizer a definite advantage for the desired application provided that it is easy to inhale the aerosol generated by the nebulizer.

The improvements made are intended on the one hand to ensure that the aerosol generated by the nebulizer can be easily inhaled and this practically without losses and on the other hand that the quantity of aerosol inhaled can be known and controlled, condition essential to avoid overdose when taking inhaled medications. These improvements are achieved by fairing the object so that liquid can only escape through an orifice or slot created in the fairing and by controlling the amount of liquid that can be inhaled.

The improvements made also allow a simplification of the device by ensuring that the pumping device intended to supply the rotating object with liquid uses the motor of the rotating object.

represents an embodiment of the system according to the invention, the nebulizer is presented from the outside in the form of a box which can be cylindrical, provided on its lateral face with a slot (1) through which the droplets diffused by the rotating object can escape. This box can also be provided with an air intake (2) and has a device, for example a push button (3), making it possible to control and monitor the operation of the nebulizer. This box is provided with a device for closing the slot and the air intake if it exists, so that it is sealed when the device is not in use. This device can be for example a ring (4) provided with orifices and sliding joints around the case on which can be fixed either a mouthpiece (5) intended to allow inhalation through the mouth, or a tube intended to allow inhalation through the nose.

shows that this case has two separate compartments. The compartment (6) contains the electronic and electrical elements of the nebulizer: the electrical source, which can be a cell or a rechargeable battery, the actuators, an electronic card making it possible to perform all the nebulizer control functions and to control the actuators . The control functions are carried out by the operator by pressing a push button (3). They will be defined later.

The compartment (7) comprises the rotating object (8), the reservoir (9) of liquid and the device making it possible to supply the disc with liquid, for example a pipe (10) coming from a peristaltic pump (11). This compartment comprises the slot (1) located in the plane of rotation of the object. This compartment can also have an air intake (2).

The liquid tank (9) can be integrated into the compartment (7). It is then supplied with liquid through an orifice fitted with a plug (12) placed in the upper part of the compartment (6) and a tube (13) passing through this compartment. The reservoir (9) of liquid can also be sold separately and be placed by screwing for example on the lower part of the compartment (7).

The nebulizer necessarily includes a device for supplying the disk with liquid. To fix ideas, the flow rates requested are very low, of the order of a few centilitres per hour. With these flow rates, supra-micrometric drops are easily obtained with discs having diameters of the order of cm. These flow rates can be easily obtained with commercial mini pumps, of the diaphragm, gear or even peristaltic pump type. In this case, the nebulizer requires two motors, one to drive the disk, another to drive the pump.

An improvement can be obtained by using only one motor for the rotation of the disc and the drive of the pump. Several possibilities are described below by way of example.

describes one embodiment. The peristaltic pump body (11) for example is rotated by the axis (14) coming out of the motor (15) driving the object (8). The differences in rotational speed between the pump and the object require that the coupling between the pump body and the object be achieved by a geared motor (16)

This improvement can also be obtained by giving the rotating object a shape such that it can fulfill the two functions of spraying liquid near its edge and supplying liquid to this surface where the spraying occurs.

This improvement requires that the lower part of the rotating object is submerged in the tank. It can be done in several ways.

describes an embodiment, in which the rotating object (8) is a solid object having a symmetry of revolution resembling a plane cone whose plane which forms the upper part is provided with a device (17) making it possible to secure it to the engine. The object is crossed from bottom to top by one or more tubes (18) characterized in that the bottom inlet of the tube is closer to the axis of rotation than the top outlet. When the object is rotated, the liquid rises naturally in the tube which acts as an elevator and comes to spread out on the upper part where it can be dispersed.

describes another exemplary embodiment. The rotary object (8) is a frustoconical object widening upwards. This object is provided with a cross-type device (19) allowing it to be fixed to the motor and ends at its upper part with a disc (20). The connection between the frustoconical part and the disc can advantageously be profiled so that the flow of liquid is the least disturbed. When the object is rotated, a vortex is created which naturally causes the liquid to rise along the internal wall of the frustoconical object and spread over the disc before dispersing.

These embodiments are given by way of illustration and other shapes can be given to the rotating object.

The assembly is designed in such a way that it is naturally held in one hand with the plane of rotation horizontal, and the tank (9) at the bottom of the compartment (7). The device can however operate without inconvenience, when the plane of rotation of the object has a certain inclination with respect to the horizontal.

Several operating modes can exist depending on the stopping distance of the drops relative to the desired distance of spraying called distance from the target and according to the latitude given to the user for the quantity of liquid to inhale.

According to a first mode of operation, the stopping distance is less than that of the target and the user is free to inhale the quantity of liquid he wants. As the stopping distance is too small, the liquid naturally cannot reach the target unless the user sucks in at the same time. According to this operating mode, the user presses the button (3) to start the rotating disc motor and the pump motor if it is independent, the liquid is sprayed, but cannot leave the compartment and falls back into the tank. If the user wants to inhale liquid, he has to inhale through the mouthpiece, in doing so he accelerates the droplets that are near the mouthpiece and enter the mouth or nose. The amount of liquid inhaled in this mode of operation depends solely on the duration and number of inhalations.

When the user wants to stop inhaling, he presses the button again, which stops the rotation of the motor of the object and of the pump if it is independent.

According to a second mode of operation, the stopping distance is less than that of the target, and the user must not inhale more than a certain quantity of liquid. As the stopping distance is too small, the liquid naturally cannot reach the target unless the user sucks in at the same time. According to this mode of operation, the user presses the button (3) to start the motor of the rotating disc and the motor of the pump if it is independent, the liquid is sprayed, but not being able to leave the compartment falls back into the tank. If the user wants to inhale liquid, he has to inhale through the mouthpiece, in doing so he accelerates the droplets that are near the mouthpiece and enter the mouth or nose. Pressing the button starts a timer. At the end of the preset time, the motor stops and if the user continues to inhale, he only inhales air.

According to a third mode of operation, the stopping distance is greater than the distance from the target and the user is free to inhale the quantity of liquid he wants. According to this mode of operation, the user triggers the nebulizer by pressing the push button, the disc starts rotating, the pump supplies it with liquid, the liquid disperses in the plane of rotation, the drops which see the slit pass through it and enter the mouth or nose. The other drops touch the walls of the case and trickle down to the reservoir part where they can be reused. The user is not required to vacuum during this phase. Nebulization is stopped by simply pressing the push button again.

According to a fourth mode of operation, the stopping distance is greater than the desired spraying distance and the user must inhale a precise quantity of liquid. According to this mode of operation, the user triggers the nebulizer by pressing the push button, the disk starts rotating, the pump supplies it with liquid, the liquid disperses in the plane of rotation, the drops which see the slit pass through it and enter the mouth or nose. The other drops touch the walls of the case and trickle down to the reservoir part where they can be reused. Pressing the button starts a timer which stops the motor at the end of the preset time.

Finally, it is also possible to provide controls intended to help the user, for example an alarm in the event of a lack of liquid or in the event of incorrect positioning of the nebulizer.

Preferably,

• the rotating object (8) is enclosed in a fairing,
• the rotating object nebulizer is fitted with a shutter (4) isolating the nebulizer when not in use,
• the rotating object nebulizer has a side opening to disturb the air inside the fairing,
• the pump body (11) coincides with the rotating object (8),
• the tank (9) is removable,
• the rotating object nebulizer is equipped with automatisms allowing the delivery of a precise quantity of liquid, independently of the will of the user.

Claims (7)

Rotating object nebulizer characterized in that the rotating object (8) is enclosed in a shroud provided with a slit (1) placed in the plane of rotation of the object allowing the droplets formed at the edge of the object to exit fairing through this slot and provided with a shutter (4) isolating the nebulizer when not in use. Rotating object nebulizer characterized in that the rotating object (8) is enclosed in a shroud provided with a slit (1) placed in the plane of rotation of the object allowing the droplets formed at the edge of the object to exit of the fairing through this slot, has a side opening allowing the air to be disturbed inside the fairing and is provided with a shutter (4) isolating the nebulizer when it is not in use. Rotating object nebulizer according to Claim 1 or 2, characterized in that a mouthpiece (5) making it possible to connect the nebulizer to the mouth or a tube making it possible to connect the nebulizer to the nose is positioned at the level of the slot (1) at the moment using the nebulizer. Rotating object nebulizer according to Claim 1 or 2, characterized in that it further comprises a pump body (11), the said pump body (11) and the rotating object (8) being set in rotation by a single and same engine. Rotating object nebulizer according to Claim 1 or 2, characterized in that it also comprises a pump body (11) coinciding with the rotating object (8). Rotating object nebulizer according to claim 1 or 2 characterized in that it further comprises a reservoir (9), said reservoir (9) being removable Rotating object nebulizer according to Claim 1 or 2, characterized in that it is further provided with automatic devices allowing the delivery of a precise quantity of liquid.