IE56449B1

IE56449B1 - Dosage device

Info

Publication number: IE56449B1
Application number: IE714/85A
Authority: IE
Original assignee: Draco Ab
Priority date: 1984-04-02
Filing date: 1985-03-20
Publication date: 1991-07-31
Also published as: NL8500799A; JPH0559744B2; PT80205B; ES8603333A1; IE850714L; DE3511817C2; IS2996A7; SE8501129D0; DE3511817A1; SE8501129L; IT8547873A1; FI851302L; GB2156783A; LU85828A1; NZ211576A; FR2561912A1; JPS60225564A; FI851302A0; DK162208B; ZA851899B

Abstract

A dosage device for dosing with high accuracy a particulate material containing a pharmacalogically active substance, including a storage chamber (4), a rotatable dosing unit (2) adjacent the storage chamber, an operating unit (1) to cause relative rotation between the dosing unit and the storage chamber, the dosing unit (2) being provided with a plurality of upwardly opening recesses (7) opening into said storage chamber (4), to receive particulate material therefrom. Scrapers (8) are positioned immediately above these recesses to pack and level the particulate material into the recesses (7) and level the material off with the upper surfaces of the recesses as the dosing unit rotates relative to the storage chamber (4) The operating unit (1) causes an indexing of the dosing unit (2) between discrete rotational positions in one of which one of the recesses (7) is in direct communication with a generally 9 upwardly extending dispensing channel (5) so that when the unit is turned upside down that recess will discharge through the channel (5).

Description

The present invention relates to a new dosage device intended to be used for dosing of micronized or granulated substances or microcapsules (hereinafter referred to collectively as particulate material) and containing pnarmacologically active substances. ί Several preparations of drugs are nowadays administered in micronized or granulated form or in the | form of microcapsules. These substances are filled into capsules of hard gelatine, which are intended for oral 10 administration and are swallowed whole by the patient.

Children and adults who have difficulties in swallowing a wnole capsule are recommended to open the capsule and spread the contents on a suitable piece of food and to swallow. It is, however, difficult to open the capsule and pour out the contents without any loss of the substance.

Capsules of hard gelatine are an expensive, but effective, way to administer pharmacologically active substances to patients, who are able to swallow the capsules unbroxen. It is, nowever, not sensible to use this expensive way of dispensing into capsules of nard gelatine, wnen the patient later on, with some difficulty, opens tne capsule and pours out the contents.

It has previously been proposed to provide dosage devices to enable the particulate material to be dispensed accurately. For example DE-A-2 052 051 describes a dosage device comprising a control unit and a storage chamber. The control unit is fitted relatively loosely to the casing of the device. Substances having small particles tnus easily fall on the sliding surfaces between the two relatively movable units, so that substance 4 being fed jams. With such a dosage device, it is difficult to dose small amounts of micronized or granulated substances witn an accuracy wnicn is sufficient Ί for the dispensing of drugs.

According to the present invention there is provided is dosage device for dosing with high accuracy a particulate material containing a pharmacalogically active substance, said device comprising a storage chamber, a rotatable dosing unit adjacent said storage chamber, an operating unit to cause relative rotation between said dosing unit and said storage chamber, 2U upside down.

With the construction according to the present invention, the substance is prevented from getting into contact with the sliding surfaces in tne two relatively movable parts of the dosage device and in this way feeding of each dose can be achieved without any problems. In tne dosage device according to the invention, the scrapers make it possible to fill tne recesses in the dosing unit in a accurately reproducaole way. A high dosage accuracy can tnus be obtained by the rotation of the dosing unit. χη order that the invention may more readily be understood, the following description.is given, merely by way of example, reference being made to the accompanying drawings, in which:Figure 1 is an exial cross-section of one embodi35 ment of dosage device according to the invention; ana Figure 2 is a cross-section taken along the line 21-11 of Figure K The dosage unit of tne present invention can be considered to comprise four separate units as follows:an operating unit 1 at the bottom of the dosage device; a spring loaded dispensing unit 2; a scraping unit 3; and a storage chamber 4 provided with a dispensing channel 5 for the dose to be dispensed.

A further separate part is shown in the drawings and is preferred, but is not essential, this being in the form of a plastic or metal hood 6 which can be retained by a peripheral rib (not shown)at the upper part of the i operating unit 1. This rib enables the hood to be removably retained. An alternative way of sealing the device is to provide a plug in the top of the dispensing Channel 5. 1 5 hl tne lower mid part of tne storage chamber 4, tne scrapiny unit 3 is fixed to tne inner wall of the r orage chamber so that it cannot rotate relative thereto. Tne scraping unit in fact includes the lower part of tne dispensing channel 5 which is formed integrally with the storage chamber 4. From Figure 2 it will be seen more clearly tnat the scraping unit 3 includes 5 radially extending arms each of wnich carries a resilient scraper 8 in sliding contact with the upper surface of tne dosing unit 2 which, in turn, is provided witn six circumferentially spaced slightly frustoconical recesses 7 positioned immediately under the scrapers 8. In order to guide for rotation che dosing unit 2, tne scraping unit has an outer peripheral skirt engaging tne cylindrical outer surface of tne dosing unit 2 and a short inner annulus engaging the upper surface of the dosing unit inwardly of the recesses 7 in order to prevent jamming at feeding. Tne dosing unit 2 is loaded by a spring 9 in order to press tne dosing unit against the scraping unit. Between the dispensing unit and the spring there is situated a disc 14 which is Keyed bo the storage chamber dosing unit and has a toothed ring 13.

The operating unit 1, against which the other end of the spring 9 abuts, carries a resilient arm 12 wnich is I I 10 » Λ engageable with the toothed ring 13. Thus the disc 14, in effect, controls the angular movement of the dosing unit 2 so that one of the recesses 7 will always stop in the correct position that is immediately below the dispensing channel 5 as shown in Figure 1. Furthermore, the disc 14 reduces the friction between the spring and the dosing unit.

In the operating unit 1 there is provided a space 10, as illustrated closed by a porous pad and into the space 10 can be inserted a drying agent sucn as silica gel in order to protect the contents of the device from the humidity of tne air. The ingress of humidity will also be reduced by the provision of the hood 6.

The particulate pharmaceutically active substance is stored inside the storage chamber 4 ana the actual dosing operation is carried out with the dosing device in the upright position shown in Figure 1, by rotating the operating unit at first counterclockwise and then clockwise. The ratcnet mechanism formed by the tootned ring 13 and the resilient arm 12 will thus index tne dosing unit so that first one and then another recess appear immediately under the dispensing channel. All of the recesses, however open into the storage chamber and can be filled with tne particulate material therein.

Thus, a predetermined amount of particulate pharmaceutically active substance can be dosed by tne correct choice of the size of the recess 7. The effect of the scrapers 8 on the scraping unit 3, past which the dosing unit recesses move,is firstly co force and pack the particulate material into cne recess and secondly accurately to level off the particulate material at the top of the recess.

This means that when a recess 7 arrives immediately below the dispensing channel 5 it will be completely ana accurately full.

All that is then necessary is to turn the dosage device upside down and the particulate material will flow down the dispensing channel 5. By choosing the size of the recess for whichever substance is to be dispensed, one can thus choose the size of a dose which may, for example be varied within wide limits, say from 1 to 5 mg or 5 to 200 mg. The number of recesses in the dosing unit may vary depending on different factors, such as 5 the amount of active substance which snould be administered in each dose, the physical properties of the active substances and so on. In a preferred embodiment, the dosing unit has six recesses and these recesses are preferably cylindrical or preferably frustoconical as shown and ' should preferably hold 1 dose of active substance.

The size of the storage chamber may be chosen to J suit the reqirements expected for a particular active substance. In a dosage device where the storage chamber cannot be refilled with active substance, the chamber may, for example,contain sufficient active substance for about 100 doses.

In an alternative embodiment the dosage device nas a resilient key which makes it possible to feed the device with one hand. Each push on the key causes indexing of the aosing device so that a recess filled with the active substance is placed in communication with the dispensing channel.

The dosage device may be used as container and aid in dispensing of a great number of active substances such as enprophylline, theophylline and terbutaline.

Example In order to demostrate the dosage accuracy of the dosage device according to the present invention the following tests have been carried out with different sizes of the recesses 7. The container was filled with Theo-Dur sprinkle substance (which is a slow release preparation of theophylline) mixed with 1 and 2% of talcum respectively. When the dosage accuracy of 500 doses was established a maximum deviation of 3.5% was obtained. cf. the table below.

I ij.

Test with seven different dosage devices containing Theo-Dur sprinkle substance mixed with talcum The figures below are the average values of 500 doses from eacn dosage device.

Dosage device Talcum 1 % 2¾ mg/doseSrel % mg/dose s <, rel % 1 104. 1 2.15 2.1 104.2 2.45 2.4 2 94.0 2.36 2.5 94.0 2.66 2.8 3 85.4 2.29 2.7 84.8 2.30 2.7 4 73,2 2.45 3.3 75.1 1.73 2.3 5 64.7 1.68 2.6 64.5 2.02 3.1 6 54.3 1.33 2.5 53.4 1.87 3.5 7 45.8 1.34 2.9 45.9 1.30 2.8 As a comparison reference is made to Pnarm. Nord, which specifies that 90% of the capsules shall have a weight which does not deviate more than 10% from the stipulated weight. The rest shall not deviate more than 20%. With tne new dosage device according to the invention these requirements are thus met with an ample margin.

Claims

1. A dosage device fox* dosing with high accuracy a particulate material containing a pharmacalogically active substance, said device comprising a storage chamber, a rotatable dosing unit adjacent said storage chamber, an operating unit to cause relative rotation between said dosing unit and said storage chamber, a plurality of upwardly opening recesses in said dosing ’ unit, at least one of which opens into said storage chamber, to receive particulate material therefrom, scrapers positioned to pack and level tne particulate ί material into the recesses and level it off with the upper surfaces of the recesses as tne dosing unit rotates relative to the storage chamber, operating means on said operating unit for causing indexing of the dosing unit between discrete rotational positions, and a generally upwardly extending dispensing channel positioned at one of said discrete positions to communicate with one of said recesses, so that said one recess may be emptied by turning said device upside down.

2. A device according to claim 1 wherein the operating unit is itself rotatable relative to the storage chamber to effect indexing of the dosing unit.

3. A device according to claim 2, wherein the operating unit can be rotated alternately clockwise and counterclockwise about the axis of rotation of the dosing unit and wherein said operating means comprise a ratchet mechanism between the operating unit and tne dosing unit, wnereby the alternate clockwise and counterclockwise rotation of the operating unit will cause indexing of the dosing unit in only one rotational sense.

4. A device according to claim 3, wherein said ratchet mechanism comprises a resilient arm on the operating unit which engages on annularly spaced teeth on the dosing unit.

5. A device according to any preceding claim, } wherein said operating unit is mounted below said dosing unit.

6. A device according to claim 5, when appendent to claim 4, wherein a disc which is keyed to the storage chamber is urged against said dosing unit by a spring engaged between said disc and said operating 5 unit.

7. A device according to any preceding claim, wherein the dispensing channel passes through the storage chamber.

8. A device according to any preceding 10claim, wherein the storage chamber has a closable inlet by means of which the storage chamber can be refilled.

9. A device according to any preceding claim, wherein the dosing unit is provided with six circumferentially spaced recesses. 15

10. A device according to any preceding claim wherein said recesses are frustoconically shaped, being wider at the open end communicating with the storage chamber.

11. A dosage unit according to claim 1 for 20 dosing with high accuracy a particulate material containing a pharmacalogically active substance, said device being substantially as hereinbefore described with reference to and as illustrated in, the accompanying drawings.