GB2233564A

GB2233564A - Medical syringe with linked barrel and plunger

Info

Publication number: GB2233564A
Application number: GB9014503A
Authority: GB
Inventors: Jonathan George Denham
Original assignee: Individual
Current assignee: Individual
Priority date: 1989-06-30
Filing date: 1990-06-29
Publication date: 1991-01-16
Also published as: GB8915023D0; GB9014503D0

Abstract

In a medical syringe a hinge connection 22 links barrel 11 and plunger 12 permitting the barrel and plunger to be packed side by side and allowing the plunger to be swung into axial alignment with the barrel and inserted into the barrel for use. A number of different forms of hinge connections are disclosed together with a two-part carton in which the syringe can be stored before use and also different forms of dispensers in which stacks of syringe containing cartons are held with different medication in a required sequence of use to be dispensed in the appropriate order of use <IMAGE>

Description

IMPROVEMENTS IN OR RELATING TO MEDICAL SYRINGES This invention relates to medical syringes.

Commonly, medical syringes are supplied for use as separate components, that is a syringe barrel and a plunger, the barrel being adapted at one end to receive a needle and at the other end being open to receive the plunger. The user has to assemble the plunger in the barrel before the syringe can be used.

Frequently, medical practioners are required to give patients injections under severe conditions of stress such as when a patient has suffered a cardiac arrest. The patient must be injected with a number of medicaments with required dosages and in a required sequence in a very short space of time each requiring a separate syringe which the medical practioner has to assemble fill and use for each injection, whilst at the same time ensuring that the correct medicament and correct dosage is given. Time can be lost and mistakes can easily occur in treating the patient because the practioner has to concentrate not only on the patient but also on correctly assembling the syringes for use.

It is an object of this invention to provide an arrangement for facilitating the assembly of a syringe ready for use.

This invention provides a syringe having a barrel, a plunger and a hinge connection linking the barrel to the plunger, the hinge connection permitting the barrel and plunger to lie side by side for packing and in alignment for the plunger to be inserted in the barrel for use.

In one construction according to the invention, the hinge access of the hinge connection is located to one side of and beyond the end of the barrel into which the plunger is inserted to facilitate assembly of the syringe.

The hinge connection to the plunger may permit sliding movement of the plunger in its lengthwise direction with respect to the connection to permit the plunger to move with respect to the connection as it is inserted into the barrel. More specifically, the hinge connection to the plunger may comprise a collar encircling the plunger and through which the plunger is slidable.

Further the hinge connection to the plunger may include scale means extending from the connection along the plunger to provide an indication of the travel of the plunger through the connection means for a particular dosage to be dispensed by the syringe. In particular the scale means may comprise an element extending from the connection means along the plunger and the plunger may have a head at the end remote from the connection engagable with the element to limit the travel of the plunger through the connection, the element being frangible or bent back at defined locations along its length according to the dose of material to be dispensed by the syringe to allow correspondingly appropriate travel of the plunger.

In any of the above arrangements, alignment means may be provided on the plunger and barrel respectively engagable by hingeing the plunger into line with the barrel to align the plunger for movement into the barrel. For example, the alignment means may comprise a projection on one of the barrel and plunger and a socket to receive the projection on the other of the barrel and plunger. More specifically, the projection may include detent means engagable with the socket to retain the projection in alignment with the barrel once engaged in the socket.

In any of the above arrangements, the hinge connection may comprise a polypropylene injection moulding with an integral live hinge providing said hinge access.

In a preferred arrangement, the barrel of the syringe is charged with the medicament to be dispensed and the end of the barrel to receive the plunger is closed by a frangible cover rupturable by the plunger as it is inserted into the barrel to dispense the medicament therefrom.

In a further arangement according to the invention, the syringe may be packed in a two part carton for holding respectively the barrel and plunger of the syringe, the carton embodying a hinge between said parts to enable the parts to be folded from a position in which they lie alongside one another with the barrel and plunger of the syringe located in corresponding positions and a position in which they are aligned and in which the barrel and plunger are correspondingly aligned.

More specifically, each carton part may comprise troughs having integral retainers to receive and hold the respective plunger and barrel of the syringe, the troughs being hinged together at one end with the sides of the respective troughs being connected together by frangible connections and the other ends of the troughs having projecting flaps to allow the troughs to be separated about the hinge axis severing the connections between the side walls of the troughs to open the troughs into alignment as aforesaid.

The invention may also include a dispenser for holding a supply of packs of syringes prefilled with medicaments to be injected in a predetermined sequence comprising a container in which the syringe packs are stacked in the required order of use starting from the bottom of the container, the container bottom being formed with a downwardly hingeable tray in which the lowermost pack resides until removed when the tray is opened to allow the next pack to drop into the tray so that the syringe packs are presented to the user in the required order of use.

The following is a description of some specific embodiments of the invention, reference being made to the accompanying drawings in which: Figure 1 is a perspective view of a syringe for injecting a medicament in a packed condition with the barrel and plunger of the syringe stored side by side with a hinge connection between the barrel and plunger; Figure 2 is a view of the syringe of Figure 1 with the barrel and plunger partly unfolded into alignment for operation; Figure 3 is a further view of the syringe with the barrel and plunger fully unfolded into alignment ready for operation of the syringe; Figure 4 is a view of the syringe with the barrel and plunger folded together as in Figure 1 showing the hinge connection between the barrel and plunger in detail;; Figure 5 is a detailed view of a modified form of hinge connection to add between the barrel and the plunger of a syringe including means for locating and locking the barrel and plunger in alignment; Figure 6 is a view of the hinge connection as shown in Figure 5 with the respective elements of the connection locked together; Figure 7 is a diagrammatic view of an upper part of the syringe barrel and plunger interconnected by the hinge connection of Figure 5 with the barrel and plunger in the folded side by side condition; Figure 8 is a similar view to Figure 7 with the barrel and plunger unfolded and locked in alignment for use; Figure 9 is a further modification of the hinge connection shown in Figure 5 with the addition of a graded depth scale to enable the amount of medicament to be dispensed by the syringe to be regulated; ; Figure 10 illustrates the trimming of the depth scale to suit the amount of medicament to be dispensed; Figure 11 is a further view of the hinge connection shown in Figure 9; Figure 12 is a perspective view of a pack for storing the syringe in folded condition; Figures 13 and 14 are detailed views of one end of the pack illustrating the manner in which the pack is opened; Figure 15 illustrates the profile of a cardboard blank from which the pack illustrated in Figure 12 is produced; Figure 16 is a front elevation view of a dispenser for a supply of syringe packs containing appropriate medicaments for a sequence of injections to suit a particular treatment and arrange to be released from the dispenser in the required order for use; Figure 17 is a perspective view of the dispenser showing the dispenser in greater detail;; Figure 18 is a view of a set of dispenser units as shown in Figures 16 and 17 containing syringe packs to cover a number of variations in a treatment type; Figure 19 illustrates the set of dispenser units shown in Figure 18 suspended from a bandelier; Figures 20 to 22 illustrate a further form of syringe construction; Figures 23 to 25 illustrate a modified form of pack or carton for storing a syringe; and Figures 26 to 29 illustrate a further form of dispenser for the cartons.

Reference is made firstly to Figures 1 to 3 of the drawings in which there is shown a syringe indicated generally at 10 comprising a cylindrical barrel 11 and a corresponding cylindrical plunger 12 to engage in the barrel.

The barrel 11 has one end 13 which is closed by an end wall 14 on which a removable needle 15 is mounted. For example the end wall may be provided with a "leuer" device 16 for easy removal and locking of a needle in place.

The other end of the barrel 17 is open to receive the plunger 12. The barrel is prefilled with a medicament to be injected and the open end 17 of the barrel is closed by a rubber bung slidable in the barrel and a plastic membrane seal covering the open end which is rupturable by insertion of the plunger into the barrel.

The plunger 12 is formed with a head 18 at one end to engage in the barrel 10 and an integral thumb bar 19 at the other end. For packaging purposes the barrel and plunger are assembled side by side as indicated in Figure 1 and may be secured together by an encircling band 20 having adhesive ends which are stuck together to form a flap 21 projecting laterally of the assembly on which the drug name, date of expiry, batch number, quantity and solution are printed, together with a corresponding bar code. The band 20 is readily ruptured by separating the barrel and plunger when required for use.

The open end 17 of the barrel and the headed end 18 of the plunger are interconnected by a polypropylene plastics hinge connection indicated generally at 22. The hinge connection comprises a collar 23 tightly fitted to the barrel 11 (so as not to be slidable along the barrel) adjacent the open end 17 thereof having an integral lug 24 on its outer surface connected by a live hinge 25 to a bar 26. A further collar 27 encircles the plunger 12 with a sliding fit to allow the plunger to move through the collar. The collar 27 also has a laterally projecting lug 28 which is connected by an integral live hinge 29 to the bar 26. Thus the collars 23 and 27 and bar 26 form a one piece interconnection between the barrel and plunger.The hinge connection permits the plunger to be folded with respect to the barrel from a side by side position shown in Figure 1 through the position shown in Figure 2 into direct alignment with the barrel. The plunger can then be pushed through the collar 27 into the barrel to inject a drug in the barrel as shown in Figure 3.

Since the barrel and plunger are interconnected, the risk of one or other of the parts of the syringe being dropped when being assembled is avoided and the hinge connection enables the plunger to be readily moved into correct alignment with the barrel ready for use.

The collar 23 is a secure fit on the barrel 11 and is formed with diametrically outwardly extending finger bars 30 on either side thereof which are moulded integrally with the collar for engagement by the fingers of the user when pressing the plunger into the barrel.

Figures 4 to 8 of the accompanying drawings illustrate a modified form of the hinge connection between the barrel and plunger. Firstly, the collar 27 is moulded with an upstanding leg 31 formed with a barb shaped end 32 and collar 23 is moulded with a laterally extending flange 33 formed with a slot 34 to receive the leg 31 which accurately aligns the plunger 12 with the barrel 11. The barb shaped end 32 on leg 31 snaps through the slot 34 to hold the leg in the slot as shown in Figure 5a. Figure 6 shows a modification of the arrangement in which the flange 34 is somewhat deeper and is formed with an internal recess 35 in which the barbed shaped end 32 on leg 31 engages.

A further modification in the hinge connection is that membrane hinge 25 is omitted and bar 26 is moulded integrally with lug 24 with the bar extending radially outwardly and axially away from the end of the barrel. The collar 27 has a integral live hinge 29 to the bar to enable the plunger to be moved from the side by side location with respect to the barrel as shown in Figure 7 into alignment with the barrel as shown in Figure 8. The hinging movement automatically engages the leg 31 in the slot 32 as described above.

Figures 9 to 11 show a further modification in which the collar 27 encircling the plunger is formed with a projecting scale member 36 to project along the barrel 12 towards the thumb bar 19. The scale member 36 forms an end stop for the thumb bar 19 as the plunger 12 is depressed into the barrel 11 to limit the travel of the plunger and thereby limit the quantity of drug injected from the syringe. The scale element 36 is formed with a series of deep grooves 37 allowing a portion of the member to be snapped off or bent back according to the amount of drug to be injected and the scale member is marked up with graduations correlating shortening of the scale member and the corresponding amount of drug which would then be injected with patient age. Thus the user is provided with a very simple and readily usable guide for the amount of drug to be injected for the patient.

Figures 12 to 14 illustrate a cardboard carton 40 for holding the syringe prior to use. In this case the paper band 20 is omitted. The carton is formed from a one piece blank indicated at 41 which, when folded and glued, forms a generally rectangular elongate box as indicated at Figure 12 comprising two trough shaped parts 42, 43 having integral retaining elemerts for the hinge and barrel and being connected at one end by a double hinge 44 and at the other end by a pair of separable flaps 45, 46. The side walls of the troughs have lines of perforations 47 so that when the flaps 45, 46 are pulled apart, the perforations break allowing the troughs to open about the hinge axis 44. In so doing the barrel and plunger of the syringe stowed in the carton side by side one another are pivoted apart into alignment ready for use as described above.

Reference is now made to Figures 16 to 19 of the accompanying drawings which illustrate a dispenser 50 for holding a supply of prefilled syringe assemblies as shown in Figure 1 stacked one above the other in the required order of use from the bottom of the stack. The dispenser 50 is formed with a bottom tray 51 hinged at the back of the dispenser and formed with an upstanding lug 52 at the front of the dispenser with a finger hole 53 to facilitate opening of the tray. The tray is hinged down in its open position to allow a pack to be removed from the bottom of the dispenser for use and the next assembly in the stack above then drops down into the tray ready for removal.

The front of the dispenser has an information panel 54 which may be marked up with the type of cardiac arrest for which the pack of drugs is intended and the set of drugs in the recommended order of administration.

A set of dispensers suitable for cardiac arrest treatment may be mounted on a bandolier 55 formed with an end tap 56 from which the pack can be suspended at a convenient location near to the patient. In the example shown three dispensers are shown for each common type of cardiac arrest. The doctor can thus readily identify the appropriate pack to be used for the particular patient and on opening the bottom tray of the pack, prefilled syringe assemblies are presented to the doctor in the required order of injection. Since the syringes are prefilled and the barrel and plunger of the syringe readily assembled into the correct working relationship, the extent to which the doctor's attention is distracted from the patient in preparing the injections is minimised.

Reference is now made to Figures 20 to 22 of the drawings which illustrate a further modified form of the syringe construction of Figures 1 to 3. For the sake of simplicity, like parts have been allotted the same reference numerals. In the arrangement shown in Figures 20 to 22, the collar 23 of the hinge connection 22 between the plunger and barrel is replaced by a C-shaped clip 60 to engage and grip the barrel 11. The end 17 of the barrel which receives the plunger 12 is formed with an oval encircling flange 61 which overlies the clip. The hinge 22 is formed as a one piece moulding with the plunger 12 for example by injection moulding in polypropylene.

The plunger 12 is formed with an integrally with the hinge connection 22, one end of the plunger being located in and connected to the collar by spaced membrane elements 64. The other end of the plunger has an integral lateralling extending arm 62 to facilitate extraction of the plunger from the syringe barrel. The membrane elements are ruptured by pressure applied to the plunger to drive the plunger through the collar into the syringe barrel. The collar 27 is formed with upstanding barb shaped clips 65 which snap into slots 66 formed adjacent the ends of the arms of the C-shaped clip 60 to lock the collar 23 over the C-shaped clip with the plunger 12 in alignment with the syringe barrel 11 ready for use as shown in Figures 21 and 22.Sufficient pressure on the plunger then ruptures the membrane elements 64 and allows the plunger to be pushed through the collar 27 into the syringe barrel rupturing the cover of the end 17 of the barrel and allowing the plunger to move into the barrel to depress the rubber bung down the barrel and thereby express the medicament to be injected from the syringe barrel. The arrangement is otherwise similar to the syringe arrangement described earlier.

Reference is now made to Figures 23 to 25 which illustrate a modified form of the carton 40 for holding the syringe prior to use. Again like parts have been allotted the same reference numerals.

Firstly the flaps 45 and 46 of the carton are waisted as indicated at 47 to cooperate with guide members in a stacking arrangement for the cartons to be described below. The ends of the flaps have a rounded D-shaped profile as indicated. A further difference is that the perforated sides of the carton are formed with "saw-tooth" shaped perforations 70.

The arrangement is otherwise similar to that described above.

Reference is now made to 26 to 29 which illustrate a dispenser 80 for holding stacks of cartons containing pre-filled syringe assemblies. A dispenser comprises a case 80 formed as a one piece plastics moulding and having front and back sections 80a, 80b connected along their lower edges by an integral membrane hinge 81 and coupled along their upper edges by integral deterts 82 formed on the upper edge of the back portion 80a which snap over and engage in integral recesses 83 in the upper edge of the front portion.

Elongate openings 84, 85 are formed in the respective front and back sections adjacent the upper ends thereof to create a handle 86 for carrying the case. The back portion 80a of the case is formed with two integral stands 87 at spaced locations along the back portion to support the case on a horizontal surface extending upwardly and slightly rearwardly.

The case is formed internally with three vertically extending channels 88, 89 and 90 by integral vertically extending ridges 91, 92 and 93 raised at opposite locations on the inner sides of the front and rear sections of the case. Stacks of cartons of the form illustrated in Figures 23 to 25 are held in the respective channels with the waisted portions of the tabs 45 and 46 of the cartons engaged between the respective ridges 91, 92 or 93 on the front and rear sections of the case as illustrated in Figure 29 to constrain the cartons to fall down the channels.

The front section of the case at the bottom of each channel is formed with a downwardly hinging flap door 95 which, when opened, provides an outlet 96 at the lower end of the case from which the syringe carton 40 at the bottom of the stack can be withdrawn. The flap door 95 is held closed prior to use by an adhesive label 97 which bears an "out of date" expiry date for the medicaments held in the corresponding channel of the case.

The stack cartons in each channel are arranged in "algorithm" style to suit the treatment procedure required. That is the stack of cartons contain various medications required for a particular treatment in the order of use. The different channels may contain medication for different treatments and the appropriate information regarding the treatment, the medication and the order of use is set out on labels on the front of the case for each of the channels.

Claims

1. A syringe having a barrel, a plunger and a hinge connection linking the barrel to the plunger, the hinge connection permitting the barrel and plunger to lie side by side for packing and in alignment for the plunger to be inserted in the barrel for use.

2. A syringe as claimed in Claim 1, wherein the hinge axis of the hinge connection is located to one side of and beyond the end of the barrel into which the plunger is inserted.

3. A syringe as claimed in Claim 1 or Claim 2, wherein the hinge connection to the plunger permits sliding movement of the plunger in its lengthwise direction with respect to the connection to permit the plunger to move with respect to the connection as it is inserted into the barrel.

4. A syringe as claimed in Claim 3, wherein the hinge connection to the plunger comprises a collar encircling the plunger and through which the plunger is slidable.

5. A syringe as claimed in Claim 3 or Claim 4, wherein the hinge connection to the plunger includes scale means extending from the connection along the plunger to provide an indication of the travel of the plunger through the connection means for a particular dosage to be dispensed by the syringe.

6. A syringe as claimed in Claim 5, wherein the scale means comprises an element extending from the connection means along the plunger and the plunger has a head at the end remote from the connection engageable with the element to limit the travel of the plunger through the connection, the element being frangible or bent back at defined locations along its length according to the dose of material to be dispensed by the syringe to allow a correspondingly appropriate travel of the plunger.

7. A syringe as claimed in any of the preceding claims, wherein alignment means are provided on the plunger and barrel respectively engageable by hingeing the plunger into line with the barrel to align the plunger for movement into the barrel.

8. A syringe as claimed in Claim 7, wherein the alignment means comprise a projection on one of the barrel and plunger and a socket to receive the projection on the other of the barrel and plunger.

9. A syringe as claimed in Claim 8, wherein the projection includes detent means engageable with the socket to retain the projection in alignment with the barrel once engaged in the socket.

10. A syringe as claimed in Claim 8 or Claim 9, wherein the plunger and socket are formed integrally with the hinge connection between the plunger and barrel.

11. A syringe as claimed in any of the preceding claims, wherein the hinge connection to the barrel comprises a collar encircling the barrel.

12. A syringe as claimed in Claim 11, wherein the collar of the hinge connection encircling the barrel has laterally projecting flanges on either side thereof to form a pressure bar for the fingers of the user when depressing the plunger into the barrel.

13. A syringe as claimed in any of the preceding claims, wherein the hinge connection comprises a plastics moulding embodying an integral membrane hinge providing said hinge axis.

14. A syringe as claimed in any of the preceding claims, wherein the hinge connection comprises a collar in which the plunger is located, a clip engaging the barrel of the syringe and an integral hinge between the collar and clip, the plunger and hinge connection being formed as a one piece plastics moulding with the plunger initially located in the collar by frangible elements which are fractured when the plunger is depressed through the collar into the syringe barrel.

15. A syringe as claimed in Claim 14, wherein the collar and clip have interengaging detent means to hold the collar and clip together with the plunger aligned with the syringe barrel.

16. A syringe as claimed in any of the preceding claims, wherein the barrel is charged with the medicament to be dispensed and the end of the barrel to receive the plunger is closed by a frangible cover rupturable by the plunger as it is inserted into the barrel to dispense the medicament therefrom.

17. A syringe as claimed in any of the preceding claims in combination with a two part carton for holding respectively the barrel and plunger, the carton embodying a hinge between said parts to enable the parts to be folded from a position in which they lie alongside one another with the barrel and plunger located in corresponding positions and a position in which they are aligned and in which the barrel and plunger are correspondingly aligned.

18. A syringe as claimed in Claim 17, wherein the carton part comprise troughs to receive the respective plunger and barrel of the syringe, the troughs being hinged together at one end, with the sides of the respective troughs being connected together by frangible connections and the other ends of the troughs each having a projecting flap to allow the troughs to be separated about the hinge axis severing the connections between the side walls of the troughs to open the troughs into alignment and thereby move the plunger and barrel of the syringe into alignment.

19. A syringe as claimed in Claim 18, wherein the two part carton is formed from cardboard and the walls of the troughs are initially integral with lines of perforations between the respective side walls which sever when pulled apart to allow the troughs to separate.

20. A dispenser for holding a supply of syringe cartons as claimed in any of the preceding claims pre-filled with medicaments to be injected in a predetermined sequence comprising a container in which the syringe assemblies are stacked in the required order of use starting from the bottom of the container, the container bottom is formed with a downwardly hingeable tray in which the lowermost pack resides until removed to allow the next pack to drop into the tray place so that the syringe packs are presented to the user in the required order of use.

21. A dispenser as claimed in Claim 20, wherein the tray has an upstanding lug at its forward end projecting above the tray to lie against the front wall of the dispenser in the closed position of the tray and, in the open position of the tray to form a stop to retain a syringe assembly in the tray until required for use.

22. An assembly of dispensers according to Claim 20 or Claim 21 mounted at spaced locations along a web for suspending the dispensers in vertical orientation for access to the syringe packs therein.

23. A dispenser for syringe holding cartons as claimed in any of Claims 17 to 19 comprising a case having a plurality of channels to receive stacks of said carton guide means being provided in the case to guide the cartons to fall vertically in the stacks and each channel having an operable flap at its lower end through which cartons in each channel can be extracted from the case.

24. A syringe substantially as described with reference to and as illustrated in Figures 1 to 3, the accompanying drawings or Figures 1 to 3 as modified by Figures 4 to 8 or 9 to 11 of the accompanying drawings.

25. A syringe pack substantially as described with reference to and as illustrated in Figures 12 to 15 of the accompanying drawings.

26. A syringe pack dispenser substantially as described with reference to and as illustrated in Figures 16 to 19 of the accompanying drawings.