A MEDICINE DISPENSING DEVICE

Abstract: The invention relates to a medicine dispensing device which includes an arrangement for resetting its dosage metering and discharging parts so as to enable a new dosage ampoule to be inserted. The dispenser is mainly comprised of a slotted and hollow housing (2) for receiving dosage ampoules (3). Arranged at the rear end of the housing is a screw-threaded device (1) which has dosing and discharging means (4) connected thereto. The ampoule is secured in the housing by the screw-threaded device in coaction with a fitting (5), by screwing the screw-threaded device into at least one screw-threaded part of the rear opening of the housing. The screw-threaded device and the ampoule can be swung radially from the housing, by virtue of the fact that subsequent to administering a dosage from the ampoule, the ampoule is able to move axially in the hollow housing, and also by virtue of the fact that this screw-threaded part is positioned so that the screw-threaded device will pass out of engagement therewith when swung radially from the housing and withdrawn to its starting position, for the insertion of a new ampoule.

Description: A medicine dispensing device Technical field The present invention relates to a device for dispens¬ ing liquid substances in metered quantities from a container, said device including a mechanism by means of which, after administering the contents of the container, the device can be easily returned to its original state, in which it is able to receive a further container and to dispense measured quantities of medicine therefrom. The invention particularly re¬ lates to the dispensing of medicines from a dosage cartridge or ampoule. According to another aspect, the invention further re¬ lates to an arrangement by means of which the dispens¬ er can be returned to its original operative state. Background of the invention One problem with known devices used to administer measured quantities of medicine, i.e. dosages, such as hypodermic syringes in particular and also devices used to administer medicines in a pulverulent or viscous dosage form, is that they lack the provision of means which will ensure that the dispensing device can be returned quickly to its original state so that a new dosage ampoule can be fitted into the device. The concept of the present invention can be readily applied to different known kinds of medicine dispens¬ ing devices which include a screw mechanism for reconstituting and/or metering and administering the content of a prefilled ampoule. Dispensers of this kind are well known in the art; see for instance US,A, ,592,745. Swedish patent specifications SE,B,465065 and SE,B,- 464797 (corresponding to EP,B,298067) describe dis¬ pensers in the form of hypodermic syringes which include a screw mechanism for displacing a plunger in a prefilled cylinder. These specifications disclose how dual-chamber am¬ poules can be reconstituted by rotating the screw. Dispensing and administering of the medicine is then effected with the aid of an arrangement which is activated by means of an operating lever. In order to return a syringe of this kind to its original state and therewith enable a fresh ampoule to be fitted and reconstituted and its contents dispens¬ ed, it is necessary to withdraw the screw mechanism manually back to its starting position. This is a time consuming task and may easily be neglected, which may result in damage to the screw mechanism or in an impairment in the metering accuracy of the dispenser. Although this problem can be overcome by constructing the dispenser, or syringe, for one-time-use only, with the intention of discarding the dispenser after having emptied the ampoule with the plunger located in its forward position, this solution is not a desirable solution, mainly for material handling reasons. Consequently, there is a need for a dispenser which includes a simple arrangement by means of which those components of the dispenser which have been active in reconstituting and/or dispensing a measured quantity of medicine, or dose, can be quickly returned to their respective starting positions after emptying the ampoule. This applies in particular to the type of hypodermic needles described above, such needles being widely used within the art. It is particularly desirable to provide an arrangement by means of which a screw-threaded actuator or like devices, such as the screw described above for in¬ stance, is returned quickly to its starting position in which the dispenser, or syringe, can be fitted with a fresh ampoule. Swedish published specification 379089 and FR,A1, 2613789 teach a number of technical solutions to the problem of moving such screw-like devices quickly with the intention of releasing or securing the devices without coming into contact with the screw threads thereof. None of these publications, however, gives an indica¬ tion as to how a screw-threaded actuator intended for dispensing a metered quantity of medicine from an ampoule or similar container can be returned to its original position for administering a new dosaςe. This problem is solved by the present invention, which provides a medicine dispensing device which includes an arrangement by means of which the screw-threaded actuator can be reset quickly and readily for renewed administration of a medicine dosage. Disclosure of the invention The medicine dispenser comprises generally a slotted housing which is constructed to receive a dosage ampoule and which includes at its forward end a dosage ampoule fitting and a dispensing conduit connected thereto. Mounted at the rear end of the housing is a screw-like device which functions to secure the am- poule in said fitting and which is connected to a dosage dispensing and discharging device. According to the invention, the dispensing device is constructed so that the ampoule and the dosage dispensing and discharging device can be swung radial¬ ly out from the housing through the slotted region thereof in a given state of the dispenser. By this is meant that after dispensing and discharging the con- tent of the ampoule, the screw device can be released from the housing by swinging the device radially about its long axis, therewith enabling the ampoule to be removed radially from the dispenser housing. As the screw-threaded discharging device is screwed down it assists in securing the ampoule in the hous¬ ing, and may also contribute towards reconstituting the ampoule content, for instance by including a known mechanism for reconstituting the content of a multi- chamber ampoule (see for instance EP,B,298067) . The dispensing and discharging device may include a plu¬ rality of mechanisms that are well known to the person skilled in this art, for instance mechanisms which are able to reconstitute the content of a multi-chamber ampoule and divide the ampoule into different, adjust¬ able dosages, and to discharge the ampoule content from the dispenser. In its simplest form, the dispens- ing-and-discharging device may consist of an axially movable plunger rod connected to the screw-threaded device. The ampoule may consist of one or more cham¬ bers of which one may contain a reconstitutable medi¬ cine in powder form and may also include displaceable plungers which are actuable by component parts of the discharge device. It lies within the general purviews of the invention to provide a number of different discharge devices and ampoules of alternative embodiments, according to the type of dispensing or metering desired. The dosage ampoule is accommodated in a space provided in the housing to this end. As before mentioned, the discharge device includes a screw-threaded device which can be screwed into the rear opening of the housing, said opening having at least one screw- threaded part. The ampoule is guided axially into a fitting provided adjacent the front opening of the housing, as the screw-threaded device is screwed into said rear opening. The ampoule can then be reconstituted and dosages for administration prepared, with the aid of the various component parts of the discharge device, in a known manner. The arrangement is such that the ampoule is able to move axially in the hollow holder when empty and, consequently, sufficient axial space is obtainable for the empty ampoule and the screw-thread * -.', device to be swung away from the housing and released, this axial movement of the ampoule in the container also enabling the screw-like discharge device to be removed from the holder. To this end, the screw-threaded device is configured so that the weight of the ampoule will cause the ampoule to fall back axially within said device through a distance sufficient to enable the ampoule to be released from the securing device and to enable the screw-threaded device to be released from the holder. The loosened screw-threaded device can now be moved free from the screw-threaded part or parts of the opening, by swinging the device radially about its long axis, and is then returned to its original posi¬ tion for fitting and dissections charging of a new ampoule. The consumed dosage ampoule can be removed radially and replaced. The screw-threaded device with connected dispensing and discharging devices can be released from the screw-threaded part or parts of said opening by swing¬ ing the device radially and by withdrawing said devic¬ es beyond said screw-threaded section or sections to their starting position for receiving a new dosage ampoule. The screw-threaded device and dispensing and discharging devices are constructed to this end in a manner described herebelow with reference to a pre¬ ferred embodiment of the invention. Brief description of the drawings So that the invention will be more readily understood and further features thereof made apparent, the inven¬ tion will now be described with reference to an exe - plifying embodiment thereof and also with reference to the accompanying drawings, in which Figure 1 illustrates a suitable exemplifying embodi¬ ment of the inventive medicine dispensing device; Figure 2 is a sectional view of the device shown in Figure 1; Figure 3A is a principle sectional view of a screw- threaded device and slotted housing having two screw- threaded parts, and shows the screw-threaded device in its starting position; Figure 3B is a principle, sectional view corresponding to the view shown in Figure 3A, with the screw-thread¬ ed device in its bottom position; Figure 3C is a principle, sectional view corresponding to the views of Figure 3A and 3B, and shows the screw- threaded device swung radially out of the housing through a slotted region thereof, and withdrawn beyond the screw-threaded parts, back to its starting posi¬ tion; and Figures 4A and 4B are principle, sectional views which show that the slotted housing may be provided with only one screw-threaded part and effect the return illustrated in Figures 3A to 3C. According to one particularly preferred embodiment (see Figures 1 and 2) the screw-threaded device with connected dispensing and discharging devices is com¬ prised of a screw l and a dispensing piston rod 4 connected thereto. When inserting a dosage ampoule 3, the screw is screwed into the hollow and slotted housing 2, which is provided in its rear opening 11 with at least one screw-threaded part 7 (see Figure 3A) , wherein the ampoule is guided into a fitting in the forward end 12 of the housing as the screw is turned in the screw thread, said fitting having the form of an ampoule securing recess 5. As will be seen from the drawings, the housing is slotted so as to enable the ampoule and the screw-threaded device to be swung outwardly therefrom. In other embodiments of the invention, the screw may be caused to coact with a plunger rod of known con¬ struction (not shown) in a manner to result in recon- stitution of the content of a multi-chamber ampoule and to dispense etered dosages of said ampoule con¬ tent. The dosage ampoule is preferably cylindrical and may be configured in a number of different ways. For instance, the ampoule may include one or several chambers and may optionally include displaceable plungers capable of being activated by means of the inventive discharging mechanism. When the screw 1 has been screwed down to its limit, the ampoule contents may be discharged through a cannula or injection needle attached to the attachment device 6 , by moving the plunger rod 4. The screw is returned to its starting position by tipping the whole of the dispensing device backwards, whereupon the ampoule is able to fall back axially through a hollow space 10 provided in the screw, so as to loosen the ampoule from the recess 5 and also from the housing. The plunger rod returns to its starting position under its own weight, and the screw is loos¬ ened from the screw-threaded parts 7 by rotating the screw radially out of contact with said parts(s) 7 and returning the screw to its starting position in the aforedescribed manner (see Figure 3C). After emptying the ampoule, the plunger rod can be moved rearwardly in an axial direction through a distance corresponding to the last dosage dispensed from the ampoule, such as to further assist the am¬ poule in its axial movement. Rearward movement of the plunger rod is limited by a shoulder 9. This enables the ampoule to be released from the housing through said groove and removed radially therefrom and a further ampoule to be inserted through an opening 13 in the housing periphery. Release of the screw from the screw-threaded parts of the housing is made possible because they have been placed at a given axial distance apart, such that the distance between said parts is greater than the diame¬ ter of the screw-threaded device when said device is swung radially through the slotted region of the housing. As a result of this positioning of the screw- threaded parts, the screw-threaded device will pass free from the screw threads when said device is swung radially and drawn back to its starting position for administering a new dosage (see Figures 3A-3C) . This return of the discharge device to its starting posi¬ tion can be further facilitated by bevelling the upper opening of the housing in a manner to form a space adapted for the discharge device when said device is swung radially and drawn to its starting position. The housing may also be provided with only one screw- threaded part. This screw-threaded part should then be placed at a suitable axial distance from the rear opening of the housing, so that the discharge device will pass free from engagement with said opening when rotated radially (see Figures 4A and 4B) . The position of respective screw-threaded parts and their configuration are adapted to each manner of construction of the holder and screw-threaded device. Such constructional embodiments are well known to the person skilled in this art and may lead to a large number of embodiments, all of which lie within the scope of the present invention. It will be understood that the invention is not re¬ stricted to the aforedescribed and illustrated exem¬ plifying embodiments thereof. For instance the afore¬ described dispensing device and mechanism can be used for rapidly returning the discharge devices of injec¬ tion needles to their original positions and for replacing empty ampoules with fresh ampoules, and with other medicine dispensing devices which include a screw mechanism. The medicine dispensing device and mechanism can t adapted for use with essentially all types of med * . ,a dispensing processes effected with the aid of differ¬ ent types of containers or dosage ampoules, such as parenteral, oral, nasal, rectal and ocular administra¬ tion of metered dosages of medicine.

Claims: QTAIVIS 1. A medicine dispensing device comprising generally a housing which is adapted to receive a dosage ampoule and which has at its front end a dosage ampoule fit¬ ting and a discharge conduit for connection with said ampoule, and further comprising a screw-threaded device which can be applied to the rear end of said housing for securing the ampoule therein, said screw- threaded device being connected to a medicine metering and discharge device, c h a r a c t e r i z e d in that the housing is slotted (13); and in that the dispensing device includes means (10) which subsequent to having administering a given dosage functions to allow the ampoule and the screw-threaded device to be swung radially through the slotted region of the housing and moved back to a starting position in which the device is able to receive a new ampoule. 2. A dispenser according to Claim 1, c h a r a c ¬ t e r i z e d in that subsequent to administering a desired dosage, said means (10) enables the ampoule to move axially in the housing, such as, in turn, to enable the screw-threaded device and the ampoule to be swung outwardly from the housing through the slotted region thereof. 3. A dispenser according to Claim 1 or Claim 2, c h a r a c t e r i z e d in that the screw-threaded device is hollow (10); in that an ampoule can be fitted into the screw-threaded device so as to be movable in the axial direction thereof; in that ar¬ ranged in the hollow part of the screw-threaded device is a discharging and metering device which is intended to act upon the ampoule and to meter and discharge the contents thereof; in that the housing has a rear opening which is provided with at least one screw- threaded arcuate part for securing the ampoule in the device with the aid of said screw-threaded device; and in that the screw-threaded device can be freed from said screw-threaded part by swinging said screw- threaded device radially, so as to enable the screw- threaded device and the discharging and metering device to be moved freely rearwardly and returned to their starting positions in which a new ampoule can be inserted and its contents dispensed and administered. 4. A dispenser according to Claim 3, c h a r a c ¬ t e r i z e d in that subsequent to dispensing its contents, the ampoule can be moved axially and rear¬ wardly in the hollow screw-threaded device to an extent sufficient to release the ampoule from engage- ment with the ampoule fitting; and in that the screw- threaded device is thereby released from the housing so as to enable the ampoule to be swung radially and therewith removed from the dispenser and replaced with a fresh ampoule through the slotted region of the housing. 5. A dispenser according to Claim 3 or Claim 4, in which the rear opening of the housing has more than one screw-threaded arcuate part, c h a r a c - t e r i z e d in that the screw-threaded arcuate parts are mutually spaced apart at a distance which is greater than the diameter of the screw-threaded device when said screw-threaded device is swung radially out of the housing and drawn back to its starting posi- tion. 6. A dispenser according to Claim 3 or 4, in which the housing is provided with only one screw-threaded part, c h a r a c t e r i z e d in that the screw- threaded part is placed at a distance from the rear opening of the housing such that the screw-threaded device will pass free from said opening when the device is swung radially from the housing and drawn back to its starting position. 7. A dispenser according to Claims 3-6, c h a r a c ¬ t e r i z e d in that the rear opening of the housing is bevelled so as to provide space for the screw- threaded device when said device is swung radially away from the housing and drawn back to its starting position. 8. A dispenser according to any one of Claims 1-7, c h a r a c t e r i z e d in that the screw-threaded device (1) is connected to a dispensing or metering plunger rod (4) which is able to return to its start¬ ing position under the influence of its own weight subsequent to dispensing the contents of the ampoule (3) ; and in that the ampoule fitting has the form of a recess (5) adapted to the shape of the ampoule. 9. A dispenser according to Claim 8, c h a r a c ¬ t e r i z e d in that this axial movement of the ampoule is achieved by virtue of the fact that subse- quent to dispensing a dosage from the ampoule the plunger rod (4) is able to move rearwardly through a distance corresponding to the dispensed volume. 10. A dispenser according to any one of the preceding Claims, c h a r a c t e r i z e d in that the dosage ampoule is cylindrical and contains one or more cham¬ bers; and in that the dispenser includes means (6) for attaching a cannula or an injection needle thereto, so as to enable the dispenser to be used for parenteral injection. 11. A mechanism for resetting a screw-threaded device having an associated dosing and discharging device which can be connected to a housing adapted to receive a replaceable liquid-containing dosage ampoule to a starting position in which a new dosage ampoule can be inserted and its contents administered, c h a r a c¬ t e r i z e d in that the dosage ampoule and the screw-threaded device can be released radially from the housing after discharging and administering the contents of the ampoule. 12. A mechanism according to Claim 11, c h a r a c - t e r i z e d in that the screw-threaded device can be swung radially from the holder partly because the ampoule is fitted so as to be movable axially in the housing subsequent to administering the contents of the ampoule and therewith release the screw-threaded device from the container, and partly because the rear opening of the housing is provided with at least one screw-threaded part which is so positioned that the screw-threaded device will pass free from their at least one screw-threaded part when said screw-threaded device is swung radially, therewith enabling said device to be returned to its starting position. 13. A mechanism according to Claim 12, c h a r a c ¬ t e r i z e d in that the screw-threaded device is hollow, such as to form a space in which the ampoule can move axially subsequent to administering its contents; and in that the dispensing and discharge device connected to said screw-threaded device in¬ cludes a piston rod which is able to move axially rearwards after administering the contents of said ampoule, therewith contributing to the axial movement of the ampoule; and in that the rear opening of the housing is bevelled so as to provide a space for accommodating the screw-threaded device when said device is swung radially out of the housing and with¬ drawn to its starting position for administering a new dosage. 14. A mechanism according to Claim 12-13, when the rear opening of the housing has more than one screw- threaded part, c h a r a c t e r i z e d in that the screw-threaded parts are spaced mutually apart at a distance which is essentially greater than the diameter of the discharge device when said device is swung radially. 15. A mechanism according to Claim 12-13 wherein the rear opening of the housing has only one screw-thread¬ ed part, c h a r a c t e r i z e d in that the screw-threaded part is placed at an axial distance from the rear opening of the housing such that the discharge device will pass free from its engagement with said screw-threaded part when said device is swung radially out of the housing.

Inventors: LEVANDER GUSTAV, LJUNGQUIST OLLE, LEVANDER, GUSTAV, LJUNGQUIST, OLLE
Applicants: KABI PHARMACIA AB
Application year: 1993
Main classification: A61M5
IPC codes: A61M5