EP0070777A1

EP0070777A1 - An improved drop counter

Info

Publication number: EP0070777A1
Application number: EP82401334A
Authority: EP
Inventors: Jean-Claude Paoletti; Jean-François Peccoux
Original assignee: Laboratories Merck Sharp and Dohme Chibret SAS; Merck Sharp and Dohme LLC
Current assignee: Laboratories Merck Sharp and Dohme Chibret SAS; Merck Sharp and Dohme LLC
Priority date: 1981-07-20
Filing date: 1982-07-16
Publication date: 1983-01-26
Also published as: ES274585U; FR2509693A1; PT75272A; PT75272B; FR2509693B1; JPS5826223A; DK326382A; ES274585Y; GR77223B

Abstract

The present invention relates to a drop counter device which is to be positioned on the opening of a container holding a liquid, characterised in that the device consists of a nipple which is to be tightly attached onto said opening and containing a substantially undeformable channel 6 connecting the inside of the container to the outside thereof, the said nipple also containing a chamber 8, of which at least one wall 10 is elastically deformable under pressure, the chamber being adjacent to said channel and in contact with the inside of the container, and the said chamber and said channel being separated by a substantially undeformable wall 9.

Description

This invention relates to a drop counter device.
Drop counters are devices which are used very widely in the administration of medicaments, in particular collyria. Collyria containing active principles are presently used to an increasing extent and they have a high pharmacological activity but are toxic and have secondary effects when the prescribed doses are not observed, in particular due to a faulty dropping action of the drop counter.
Drop counters which are presently used may be divided into two groups.
The first group comprises devices which have a tube surmounted by a nipple and are integral with a cap which is usually screwed onto the container. The assembly of tube, nipple and cap has to be removed for use as a drop counter.
This type of device has numerous disadvantages. In particular, it is fairly burdensome because it requires the production and assembly of at least three distinct parts.
Moreover, there is a risk of the drop counter being positioned on a contaminated surface after use, the effect of which is to contaminate all of the product when the drop counter is replaced in the bottle.
Finally, the presence of a tube which is often very long and which has to be held by one of its ends means that this type of drop counter is difficult to use for dropping a liquid into the eye with precision.
It is for this reason that nipple-type drop counters are preferably used, in particular for administering collyria, these drop counters being tightly attached onto the opening of the container, which is usually a bottle containing the medicament in liquid form.
Use of this type of device requires turning the bottle upside down, and the liquid then fills the nipple and is ejected through a hole in the nipple by pressing on the nipple.
In the devices which are presently available, the liquid is ejected by the deformation of a hollow nipple which is pierced at the end by a hole. Direct pressure on the liquid generally results in a stream of liquid being ejected, not drops.
Moreover, it is very difficult with this type of device to ensure the delivery of a predetermined quantity of liquid.
On the other hand, if it is required to eliminate the stream effect as-far as possible, it must be possible for the size of the opening in the nipple to be of the order of from 0.5 to 0.8 mm. Under these conditions, the risks of obturation as a result of one of the components of the mixture being deposited are quite considerable.
It is for this reason that the present invention proposes a drop counter device in which the dropping action is improved. Moreover, in the device according to this invention, the presence of a chamber of determined volume allows a predetermined quantity of the product to be delivered by pressure on this chamber.
Finally, the device according to the present invention has the advantage that a delivery channel for the liquid may be used which is of a fairly large diameter, of the order of from 1 to 1.5 mm, which greatly reduces the risks of obturation.
In order to achieve this object, the present invention proposes a drop counter device adapted to be positioned over the opening of a container holding a liquid, characterised in that the drop counter device consists of a nipple adapted to be tightly attached onto said opening and containing a substantially undeformable channel connecting the inside of the container to the outside thereof, the said nipple also containing a chamber, of which at least one wall is elastically deformable under pressure, the chamber being adjacent to said channel and in contact with the inside of the container,, and the said channel and said channel being separated by a wall which is substantially undeformable.
The largest dimension of the chamber preferably extends substantially parallel to the axis of the channel and the said chamber is completely situated in one of the half-spaces defined by a plane passing through the axis of the channel.
Moreover, in order to facilitate gripping of the device, the nipple comprises two substantially flat parts which are positioned on both sides of the channel, one of these parts being positioned on the elastically deformable part of the chamber wall.
In a preferred embodiment of this device, when it is to be used to administer a medicament, the volume of the chamber is calculated so that a complete pressure delivers a dose or a complete submultiple of a therapeutic dose of said medicament.
Another advantage of the device according to the present invention is that it may be moulded in a single piece from a supple and elastic material, such as, for example, natural rubber or synthetic rubber.
In this device, the channel is preferably in the shape of a truncated cone, the widest part of which is positioned towards the inside of the container. Finally, the internal diameter of the channel at its end in contact with the exterior is preferably from O.b to 2 mm, especially from 1 to 1.5 mm.
Other advantages and characteristics of the present invention will be revealed from reading the description of the accompanying Figures, in which:

Figure 1 illustrates a section of a device according to the present invention, along AA of Figure 2,
Figure 2 illustrates a left-hand view of the device according to the invention, and
Figure 3 illustrates a top view of the device of Figure 1.

The device according to the invention illustrated in Figures 1 to 3 comprises a base 1 surmounted by a body 2 and a head 3.
The base 1, which is substantially cylindrical in shape, has a cavity 4 inside, the cross section of which is similar to or smaller than the cross section of the opening of the bottle on which the base 1 is to be appliea.
This base 1, the external diameter of which is greater than that of the body 2, allows the device to be attached on to the bottle by means of one or.more connection elements which rest on the edge 5 and on a corresponding part of the bottle.
The said base 1 is surmounted by a body 2 and by a head 3 which are pierced along their vertical axis by a channel 6 which is in contact with the cavity 4 of the base and which issues outside through an outlet tube 7.
A chamber 8 is positioned on one side of the bony 2 of the device and it extends substantially parallel to the channel and is separated therefrom by a practically undeformable partition 9. The chamber 8 is in contact with the hollow part 4 of the base. The external wall 10 of said chamber 8 is thin so that it may be deformed simply by external pressure.
In order to improve gripping of the device and to facilitate the positioning of the outlet tube during use, in particular when level with the eye, the part of the body 2 opposite the chamber 8 comprises a flat surface 11; likewise, the external face of the chamber is also flattened on a surface 12.
In the embodiment shown, the deformable chamber only occupies a restricted part of the whole of the device and its volume is determined as a function of the characteristics of the liquid to be delivered, so that a complete pressure on the chamber only delivers a determined volume of liquid which preferably corresponds to a therapeutic dose or to a complete submultiple of the therapeutic dose.
Of course, it is possible to modify the dimensions of this chamber, which will be calculated to allow the delivery of determined quantities of liquid when the chamber is completely deformed.
The device as it has been described may be attached onto a bottle by any appropriate means and, in a variation of the device, it is possible for the base of the device to be provided with a circular groove to allow it to be directly and tightly attached onto a circular boss provided on the periphery of the opening of the bottle.
Experiments which have been carried out using this type of device have shown that an excellent dropping action is simultaneously obtained over a very large viscosity range and furthermore that pressure on the chamber of the device delivers a determined and reproducible quantity of the product.

Claims

1. A drop counter device adapted to be positioned on the opening of a container holding a liquid, characterised in that the drop counter consists of a nipple adapted to be tightly attached onto said opening and containing a substantially undeformable channel 6 connecting the inside of the container to the outside thereof, the said nipple also containing a chamber 8, of which at least one wall 10 is elastically deformable under pressure, the chamber being adjacent to said channel and in contact with the inside of the.container, and the said chamber and said channel being separated by a substantially undeformable wall 9, and that said channel 6 has a fairly large internal diameter.

2. A device according to claim 1, characterised in that the largest dimension of the chamber extends substantially parallel to the axis of the channel.

3. A device according to one of claims 1 and 2, characterised in that the chamber is completely situated in one of the half-spaces defined by a plane passing through the middle axis of the channel.

4. A device according to one of claims 1 to 3, characterised in that the nipple comprises two substantially flat parts which are positioned on both sides of the channel, one of these flat parts being located on the elastically deformable part of the chamber wall.

5. A device according to one of claims 1 to 4, characterised in that the channel has the shape of a truncated cone, the widest part of which is located towards the inside of the container.

6. A device according to one of claims 1 to 5, characterised in that the nipple is moulded in a single piece.

7. A device according to one of claims 1 to 6, characterised in that the internal diameter of the channel at its end in contact with the outside is from 0.8 to 2 mm.

8. A device according to claim 7, characterised in that the internal diameter of-the channel at its end in contact with the outside is from 1 to 1.5 mm.

9. A device according to one of claims 1 to 8, characterised in that the liquid which is used is a medicament and that the volume of the chamber is calculated so that a complete pressure delivers a dose or a complete submultiple of a therapeutic dose of said medicament.