Device for dispensing a pulverulent product

Device for dispensing a pulverulent product having a reservoir unit (100) connected on the one hand, to an air expulsion system (200) and on the other hand to a dispensing head (300) provided with a dispensing orifice (310). The reservoir unit (100) has a reservoir (110) having substantially the form of a hollow cylinder, with a distal opening (111), a proximal opening (112), and a metering passage (113) connecting the distal and proximal openings (111, 112), a one-way valve (115) being positioned between the metering passage (113) and the distal opening (111), the proximal opening (112) of the reservoir (110) forming a filling cone which tapers towards the metering passage (113) to facilitate filling of the metering passage (113) with a dose of powder.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a National Stage of International Application No. PCT/FR20201/050124 filed Jan. 25, 2021, claiming priority based on French Patent Application No. FR2000769 filed Jan. 27, 2020.

FIELD OF THE INVENTION

The present invention relates to a device for dispensing a pulverulent product, in particular intended for the administration of pharmaceutical product in the form of powder on small animals, such as, for example, rodents, in particular mice.

BACKGROUND

The devices of the state of the art used to administer doses of powder on small animals, such as rodents, in particular mice, generally comprise a reservoir containing one single dose of powder, associated with a dispensing head on the one hand, and an air expulsion system on the other hand. During actuation, the air expulsion generates a pressurised airflow which enables to expel the dose of powder through the dispensing head, then generally through a cannula intubated in the animal to dispense the powder on its carina of trachea.

These devices generally have disadvantages. Thus, after each actuation, the empty reservoir must be replaced with a full reservoir, which is not practical for the handler, nor economical. A solution to resolve this problem is to provide a reusable reservoir, for example which could easily be filled with another dose of powder and assembled in the device before each actuation.

Another disadvantage relates to the air expulsion, generally done by a syringe containing air. With this type of air expulsion, the pressurised airflow generated during the actuation is dependent on the way in which the user actuates the device, in particular of the force with which they perform its actuation. This does not enable to perform a dispensing reproducible upon each actuation. A solution to resolve this problem is to use a pump adapted to generate a pressurised airflow, the actuation of this pump being independent of the force exerted by the user, in particular of the speed at which they perform this actuation.

Documents WO2019054121 and WO2012105236 describe devices of the state of the art comprising prefilled and single-use reservoirs.

SUMMARY OF CERTAIN ASPECTS OF THE INVENTION

The present invention aims to provide a powder dispensing device which does not reproduce the abovementioned disadvantages.

The present invention in particular aims to provide a powder dispensing device which enables to dispense several doses in several successive actuations.

The present invention also aims to provide a powder dispensing device which enables to easily fill the reservoir with a dose of powder before each actuation.

The present invention also aims to provide a powder dispensing device which is simple and reliable to use, with a dispensing reproducible upon each actuation.

The present invention also aims to provide a powder dispensing device which is simple and inexpensive to manufacture and to assemble.

The present invention thus provides a device for dispensing a pulverulent product comprising a reservoir unit connected on the one hand, to an air expulsion system and on the other hand to a dispensing head provided with a dispensing orifice, said reservoir unit comprising a reservoir having substantially the form of a hollow cylinder, with an opening that is distal relative to said dispensing orifice, an opening that is proximal relative to said dispensing orifice, and a metering passage connecting said distal and proximal openings, a one-way valve being positioned between said metering passage and said distal opening, said proximal opening of said reservoir forming a filling cone which tapers towards said metering passage to facilitate filling of said metering passage with a dose of powder.

Advantageously, said reservoir is fixed in a cylindrical body comprising a central passage enabling to connect said air expulsion system with said reservoir.

Advantageously, the reservoir is fixed in said cylindrical body with interposition of a seal.

Advantageously, said cylindrical body is made of metal, in particular, made of stainless steel.

Advantageously, said reservoir is made of metal, in particular, made of stainless steel.

Advantageously, said one-way valve is of the split membrane type which only opens in one single direction under the effect of a predetermined pressure.

Advantageously, said air expulsion system comprises an air pump.

Advantageously, said dispensing head comprises a dispensing member provided with said dispensing orifice.

Advantageously, said dispensing member is a needle.

Advantageously, said needle is curved or bent.

DETAILED DESCRIPTION OF NON-LIMITING EMBODIMENTS OF THE INVENTION

The terms “proximal” and “distal” are relative to the dispensing orifice. The terms “upstream” and “downstream” refer to the flow direction of the fluid product during its dispensing. The terms “axial” and “radial” are relative to the longitudinal central axis of the device.

The fluid product dispensing device represented in the Figures comprises a reservoir unit100which could contain a dose of pulverulent product, connected on the one side to an air expulsion system200and on the other side to a dispensing head300provided with a dispensing orifice310.

The reservoir unit100, more particularly visible inFIGS.12and13, comprises a reservoir110having substantially the form of a hollow cylinder, with a distal opening111, a proximal opening112and a metering passage113connecting said two distal and proximal openings111,112. A one-way valve115is arranged between said metering passage113and said distal opening111.

The reservoir110is intended to be filled with a dose of powder before each use of the device. This filling is generally done manually by the user from a powder storage container, through the proximal opening112. The reservoir110is thus reusable.

Thus, when the reservoir110is filled with a dose of powder through the proximal opening112, this dose of powder remains in the metering passage113, the one-way valve115preventing it from exiting through the distal opening111. When the air expulsion system200is actuated, a pressurised airflow is sent into the reservoir110through said distal opening111, causing the opening of the one-way valve115and the expulsion of the dose of powder through the proximal opening112.

The reservoir110is preferably fixed in a cylindrical body105comprising a central passage106enabling to connect the air expulsion system200with the reservoir110.

As visible inFIG.13, the proximal opening112of the reservoir110forms a filling cone which tapers towards said metering passage113to facilitate the filling of the metering passage113with the dose of powder. Indeed, the doses intended for small animals, such as rodents, are generally very small, typically of around a few mm3. Advantageously, it is the volume of the metering passage113which defines the volume of the dose of powder dispensed upon each actuation. This elongated tubular shape extended of the metering passage113enables in particular to limit the risks of agglomeration of the powder.

The reservoir110is advantageously fixed in the cylindrical body105with interposition of a seal107.

The one-way valve115can be of the split membrane type which only opens in one single direction under the effect of a predetermined pressure. Other implementations, for example a ball, are possible.

Such a reservoir unit100in particular enables to easily perform a sterilisation in an autoclave.

Advantageously, the reservoir110is made of metal, in particular, made of stainless steel. This enables to avoid the use of plastic materials in the expulsion path of the powder. The cylindrical body105can also be made of metal, in particular made of stainless steel. In this way, the reservoir unit100can easily be connected to the ground to avoid or limit static electricity phenomena.

The dispensing head300comprises a hollow body301fixed to the reservoir unit100by a fixing ring302.

The fixing ring302is fixed on the cylindrical body105of the reservoir unit100, for example by screwing, snap-fitting or crimping. Any other fixing means is possible.

The hollow body301comprises a central axial passage303, connected on a side to the proximal opening112of the reservoir110and on the other side to a dispensing member311provided with a dispensing orifice310. In the example represented, the dispensing member311is a needle, which can be curved or bent. In a variant, a dispensing member enabling to deliver an aerosol could be considered.

Advantageously, a hollow stopper305is interposed between the reservoir110and the hollow body301, said hollow stopper305having a conical shape adapted to the shape of the proximal opening112of the reservoir110. This hollow stopper305enables to ensure a good connection between the reservoir110and the hollow body301, in particular a sufficient sealing to avoid any loss of dose during the dispensing of a dose of powder.

The air expulsion system200can be, in a known manner, an air-filled syringe, the actuation of the piston generating a pressurised airflow.

Preferably, however, the air expulsion system200comprises a pump, of which the actuation is independent of the actuation force exerted by the user. Thus, the pressurised airflow generated upon each actuation is always identical and reproducible from one actuation to the other.

An advantageous example of the air expulsion system200will now be described in more detail in reference toFIGS.1to11.

In this example, the air expulsion is formed by a pump200comprising an external body210provided with a handle211and a dispensing nozzle215. The external body210contains a pump body comprising a pumping chamber225, and in which there is arranged a rod230acting as a piston. The rod230is fixed with respect to the external body210, and the pump body is axially movable to slide around said rod230between a rest position and an actuation position.

The pump body comprises a proximal hollow body220and a distal hollow body270, which are fixed to one another, in particular by screwing. A body seal260is provided between the proximal and distal hollow bodies to ensure a sealing fixing to one another. The proximal hollow body220comprises a proximal pump body part221and a distal pump body part222of which the inside diameter is greater than that of said proximal pump body part221. The distal hollow body270extends at least partially in the proximal hollow body220.

Said rod230comprises a proximal rod part231, a central rod part232and a distal rod part233. The outside diameter of said central rod part232is greater than the diameters of the proximal231and distal233rod parts. The central rod part232supports a first seal237and a second seal236, and the distal rod part233supports a third seal235. The proximal rod part231comprises a central passage234which extends from the dispensing nozzle215into the central rod part232beyond said first seal237and which opens laterally to the outside of said central rod part232between said first and second seals237,236. The distal rod part233slides in said distal hollow body270, said third seal235performing the sealing therebetween during actuation.

The distal hollow body270contains at least one spring240,241collaborating on the one hand with the distal rod part233and on the other hand with the distal hollow body270. In the example represented in the drawings, there are two springs240,241arranged axially behind one another by being connected by a connecting member245. Naturally, one single spring can be considered.

Possibly, an adjustment element250, such as an adjustment screw, can be arranged in the distal hollow body270to form the contact with the spring240. This adjustment element250thus enables to easily modify the actuation force exerted by the spring(s) on the rod230during the actuation.

FIGS.5to10illustrate an advantageous actuation cycle of this air pump.

In the rest position, represented inFIG.5, the pump body is urged axially towards the outside of the external body210by the springs240,241, the first and second seal237,236collaborate in a sealed manner with the proximal pump body part221of the proximal hollow body220. The dosing chamber225is therefore isolated from the dispensing nozzle. The third seal235is arranged outside of the distal hollow body270, such that the dosing chamber225is open to the atmosphere via the distal hollow body270.

When the user exerts an axial thrust force on the distal hollow body270, as illustrated by the arrow P inFIG.6, the pump body, formed by the proximal hollow body220and the distal hollow body270, slides axially towards the inside of the external body210, around the rod230. As can be better seen inFIG.11, the third seal235thus collaborates in a sealed manner with the internal surface of the distal hollow body270, to thus isolate the dosing chamber225from the atmosphere.

A continuation of the axial thrust force P such as illustrated inFIG.7thus causes the compression of air in the dosing chamber225, under the effect of the central rod part232of a larger diameter which progressively penetrates into the dosing chamber225. When the seal seal236reaches the distal pump body part222of a greater diameter and ceases to collaborate in a sealed manner with the proximal pump body part221, the compressed air contained in the dosing chamber225can escape around the central rod part232to the central passage234then to the dispensing nozzle215, as illustrated by the arrow D inFIG.7.

FIG.8shows the position at the end of the actuation stroke, after expulsion of the compressed air contained in the dosing chamber225. In this position, the proximal axial end of the distal hollow body270abuts against the shoulder formed between the distal rod part233and the central rod part232. This mechanical abutment of the actuation stroke of the pump ensures an actuation independent of the force exerted by the user.

When the user relaxes their pressure on the pump body, the spring240,241which has been compressed during the actuation stroke, expands, which returns the pump body to its rest position, as illustrated by the arrow R inFIG.9. As soon as the second seal236again collaborates in a sealed manner with the central rod part232, the dosing chamber225is again isolated from the dispensing nozzle215, such that there is no other risk of re-suctioning of fluid product or air from the treated animal, despite the depression which is created in the dosing chamber225during the return stroke.

As soon as the third seal235ceases its sealed collaboration with the internal surface of the distal hollow body270, the dosing chamber225again opens towards the atmosphere generating a venting flow through the distal hollow body270, represented by the arrow E inFIG.10.

The pump is thus ready for another use.

Although the present invention is described above with reference to an advantageous embodiment, naturally various modifications can be applied thereto by the person skilled in the art, without going beyond the ambit of the present invention, as defined by the accompanying claims.