IL46017A

IL46017A - Two-chamber mixing syringe

Info

Publication number: IL46017A
Application number: IL4601774A
Authority: IL
Original assignee: Ampoules Inc
Priority date: 1974-11-07
Filing date: 1974-11-07
Publication date: 1977-11-30

Description

TVO-CHAMBER MIXING SYRINGE TWO-CHAMBER MIXING SYRINGE ABSTRACT OF THE DISCLOSURE Two-chamber syringes for mixing a powdered medicament with a diluent and then injecting the mixed ingredients into a patient are disclosed, together with a technique for assembling those syringes. According to one aspect of the invention, the syringe includes a vial formed with a single glass cylinder closed at one end by a plunger and at its other end by a pierceable diaphragm. An intermediate pierceable diaphragm divides the cylin der into upper and lower chambers, and is locked against axial movement relative to the cylinder. A powdered medicament is provided in the upper chamber and a diluent is provided in the lower chamber. The ingredients are mixed by inserting the vial into a cup-shaped holder having a hollow, pointed needle extending from the base of the holder. Axial pressure on the vial causes the pointed end of the needle to sequentially pierce the end and intermediate diaphragms, and to cause the diluent to flow into an opening in the sidewall of the needle, through the needle, and then into the upper chamber from the pointed needle end.

The thus-mixed ingredients are dispensed by applying axial pressure to the plunger, or by drawing metered amounts into the medicament pressurizing chamber of a needleless, hypojet injector.

According to another aspect of the invention, the syringe includes a vial formed from two glass cylinders or two, necked glass tubes. The glass cylinders are axially butted against an intermediate diaphragm and an end diaphragm and a plunger close the non-butted ends of the cylinders. The cylinder closed by the plunger is provided with a powdered medicament and the cylinder closed by the end diaphragm is filled with a diluent. A transparent plastic tube telescopingly embraces the cylinders and the entire assembly is mounted in a cup-shaped holder. The necked ends of the glass tubes are butted against an intermediate diaphrag or are each provided with their own diaphragm or stopper. The necks are banded together and a diluent is provided in one tube while a powdered medicament is provided in the other tube. The the two medicaments. An injection may be effected by further depressing the plunger to the end of its stroke while holding the ampoule against the skin of the patient.

While contained-needle type injection devices are suitable for many injection purposes, many physicians and nurses prefer to perform an injection with a more conventional syringe having an external needle which is manually inserted into the skin of the patient, since contained-needle type devices are primarily suited for use in a mechanical spring-actuated appli cator. While the use of applicators has many advantages, it is j impossible to express air from the ampoule prior to an injection and is impossible to aspirate the syringe during an injection to ensure that a blood vessel is not pierced by the needle. Also, applicators are not entirely suitable for veterinary use, since animals vary in size and coat.

In view of these problems, attempts have been made to provide two-chamber syringes having an external needle which are j! adapted to perform a standard injection after mixing the medicaments within the syringe. For example, U.S. patent No. 3,342,180 provides a vial which is separated into two chambers by a plunger, !j Powder is provided in a lower chamber and liquid is provided in the upper chamber. The plunger is provided with a one-way check valve so that upon retraction of the plunger, the liquid is forced through the valve and into the compartment containing the powder. cN ENNY. FARR I NGTON , cNENNY, jhydraulically locked in position and would be moved by the piercing jneedle upon engagement. Furthermore, the device shown in that patent is not capable of having air expressed from the mixed jmedicament chamber prior to an injection, since air would be i Itrapped between the opening at the end of the needle and the intermediate diaphragm upon plunger movement.

SUMMARY OF THE INVENTION I This invention provides a two-chamber mixing and Iinjecting syringe having, or capable of being provided with, an i ! external needle which overcomes these prior art problems. i jAccording to one aspect of the invention, the syringe includes I a cylindrical, glass vial closed at one end by a plunger which Jis slidable relative to the vial and is closed at its other end 'by a pierceable diaphragm. An intermediate diaphragm divides the ivial into first and second chambers, and that diaphragm is locked i j against axial movement relative to the vial. The lock is pref- I j|erably a circumferential indentation in the sidewall of the vial to reduce the cross sectional area of the vial at that location.

The intermediate diaphragm has a groove which is engaged by the indentation. A powdered medicament is provided in the chamber between the intermediate diaphragm and the plunger and a diluent is provided in the other chamber. These ingredients are mixed by inserting the vial in a cup-shaped holder having a hollow, pressure on the vial causes the pointed end of the needle to sequentially pierce the end and intermediate diaphragms. The locking means ensures that the intermediate diaphragm will not be moved by the piercing needle. Diluent flows into an opening in the sidewall of the needle, through the needle, and then into the chamber containing the powdered medicament from the pointed needle end. The mixed ingredients are dispensed by applying axial pressure to the plunger.

Restraining intermediate diaphragm movement toward the end diaphragm is important in those situations where the powdered medicament is lyophilized in its chamber. Since the diluent is frozen and then thawed during the lyophilization cycle, an expansion takes place when the diluent is frozen and then a contraction of the chamber takes place upon thawing. If the intermediate diaphragm is not locked against movement toward the end diaphragm, the intermediate diaphragm and the end diaphragm tend to move together during the thawing operation, to thereby change the predetermined location of those two diaphragms. A precise and predetermined positioning of the end and intermediate diaphragms relative to each other and relative to the needle is important for proper piercing and mixing operations.

A wire clip surrounds the vial and has ends which are pointed and which drag along the sidewall of the cup-shaped plastic holder during the mixing operation. Reverse movement of the open end of the cup-shaped holder and which tend to dig into the sidewall if one attempts to pull the cylinder 11 out of the holder 25.

The cylinder 11 is inserted into the open end of the bore until the prongs 30 snap over a rim 31. In this position, the end diaphragm 13 abuts or is slightly spaced from a pointed end 32 of a diaphragm piercing hollow needle 33, which is received within a conically recessed portion 34 of the end diaphragm 13.

The needle 33 has a window opening 35 therein and is rigidly mounted coaxial with respect to a cylindrical, projecting end abutment portion 36 on the base 27. The base of the needle 33 terminates in a tapered nib 40.

In fluid communication with the interior of the needle 33, is a hollow injection needle 41 having a pointed injection end 42.

To maintain the sterility of the injection needle 41 and to protect the user, a combination needle guard and plunger actuator 43 encases the needle 41 and frictionally engages the tapered nib 40 which depends from the bottom of the holder 25. For reasons which will hereinafter become apparent, the pointed end 42 of the needle 41 is embedded in a soft rubber plug 45 in the actuator 43. It will be appreciated by those skilled in the art that the needle 41 need not be intimately associated with the holder 25, but may comprise a standard detachable needle having an end fitting which frictionally engages the tapered nib 40 18 collapses or is collapsed to substantially zero volume, as illustrated in Figure 3. It may be noted that with the component parts of the syringe 10 in the positions illustrated in Figure 3, the axial extent of the window opening bridges the pierced portion of the intermediate diaphragm 16 to ensure complete evacuation of the chamber 18.

After the chamber 18 has been fully collapsed and the powdered and liquid medicaments mixed in the chamber 17, the actuator 43 is removed and one threaded end 61 of the actuator 43 is threaded onto a stud 62 which is molded into the plunger 12. Prior to an injection, the syringe 10 may be inverted and any air trapped in the chamber 17 may be expressed from the needle 41 by placing the index and middle fingers on holder flanges 63 and 64 and advancing the plunger 12 by placing the thumb on a head portion 65 of the actuator until a few drops of medicament are expressed from the pointed end 42 of the needle. This operation is facilitated by providing a conical recess 66 in the intermediate plunger 16 to ensure that air will be trapped in the area of the opening 35 ahead of the rising column of medicament.

An injection may then be performed by inserting the pointed end 42 of the needle into the skin of the patient. If desired, the syringe 10 may be aspirated by retracting the plunger slightly and noting whether or not blood is drawn into j!I be made from a transparent or translucent plastic material so ^ j ; that aspiration may be observed. The chamber 17 is substantially completely evacuated by movement of the plunger 12 into contact with the intermediate diaphragm 16 since the plunger 12 has a conical surface 67 which mates with the conical recess 66 in the intermediate diaphragm 16. Furthermore, an axial recess 68 is provided in the plunger 12 to receive the pointed end of the piercing needle 33.

Other arrangements may be provided to lock the inter¬ mediate diaphragm against movement at least toward the plunger j: 12. For example, in Figure 4 there is illustrated an intermediate jj diaphragm 70 which is locked relative to a cylinder 71 by a radially projecting rib 72 on the diaphragm 70 which cooperates with a radial bulge 73 in the sidewall of the cylinder 71.

Referring now to Figure 5, there is illustrated a two- chamber vial 300 according to a further aspect of the invention.

The vial 300 includes two cut glass tubes 301 and 302. The use of cut tubing greatly minimizes the cost of the unit since such tubing is less expensive than tubing having beaded end portions.

An intermediate diaphragm means comprises a flanged rubber stopper 303 closing one end of the tube 301 and a flanged stopper 304 closing one end of the tube 302. The tubes 301 and 302 may be respectively filled with a powdered medicament and a diluent at separate locations and respectively provided with a plunger 305 and an end diaphragm 306. In order to form the vial 300, the which are similar to the component parts illustrated in the embodiment of Figures 1 through 3 and those similar parts are provided the same reference numerals. A compression spring 501 is positioned within an abutment means 502 to surround a diaphragm piercing needle 503. It may be noted that the needle 503 does not have a window opening but has a bevel which will span the thickness of the pierceable portion of the intermediate diaphragm.

The syringe 500 may be activated by applying axial pressure to the rim guard 52 at the upper end of the cylinder 11 to apply axial force to the cylinder. As this axial force is applied the cylinder moves downwardly toward the base 27 and the force causes the pointed end 504 of the needle 503 to pierce the diaphragm 13 and to enter the second chamber 18 while the spring 501 is compressed between the diaphragm 13 and the base 27.

Further axial movement of the cylinder causes further compression of the spring 501 and causes the needle 503 to pierce the intermediate diaphragm (Figure 9) . As soon as the end of the needle enters the first chamber 17 and with a relatively long beveled portion providing fluid communication between the chambers 17 and 18 , the hydraulic lock in the chamber 18 is relieved and the stored energy in the spring drives the end diaphragm 13 toward the diaphragm 16 to force the diluent into rib 21c in the sidewall of the cylinder 11c and a circumferential groove 22c in the exterior sidewall of the cylinder 11c. The rib 21c cooperates with a circumferential recess 23c in the diaphragm 13c to securely lock the diaphragm 13c in its illustrated position. An injection may be performed by inserting the cylinder 11c in a cup-shaped holder and applying axial force to the cylinder 11c so that the pointed end 126 of the needle 125 pierces the end diaphragm 13c and then applying axial force to the plunger 12c to express medicament through the j injection needle. Although the window opening 128 in the needle j 125 is not absolutely essential for injecting the medicament 20c, I it is desirable to provide such an opening so that air may be j j properly expressed from the unit prior to an injection. J i Therefore, the window opening should be spaced above the base i of the cup-shaped holder a distance which slightly exceeds the thickness of the pierceable portion of the diaphragm 13c.

Referring now to Figures 13 through 17, there is illus- j trated a technique for filling the cylinder 11 with a liquid diluent and a powdered medicament, and for assembling the diaphragms and plunger therein. The assembly technique includes the initial step of inserting the end diaphragm 13 into the non-beaded end (or upper end of the cylinder as viewed in Figure 13) by a suitable cylindrical tool until the end diaphragm attain I the position illustrated in Figure 13 slightly above the pro- j jection 21. A metered amount of the diluent 20 is then introduce |into the patient rather than injection by a needle directly associ- ,ated with the vial 200. For example, the diaphragm piercing needle ijnay communicate with tubing which in turn communicates with an I.V. jpn the cylinder to ensure that the end diaphragm will not be

Claims

Appln. 46017/2 What we claim is:

1. A two-chamber mixing syringe comprisingj vial means; a plunger slidable within and closing one end of the vial means; an end diaphragm dosing the other end of the vial means; a stationary intermediate diaphragm within said vial means separating the interior of the vial means into fire*t and second chambers respectively defined by said plunger and intermediate diaphragm and by said intermediate diaphragm and said end diaphragm said vial means and intermediate diaphragm having coacting parts that comprise means for locking the intermediate diaphragm against axial movement towards said plunger during a mixing operation and during a dispensing operation; said coacting parts comprising radially extending interen- gaging and interfering surfaces on said vial means and said intermediate diaphragm; a cup-shaped holder having a cylindrical bore closed at one end and receiving said other end of said vial means with said other end of said vial means spaced from said closed end of said bore and hollow needle means having a pointed end within the space between said other end of said vial means and said closed end of said bore, whereby an ingredient in said first chamber may be mixed with an ingredient Appln. 46017/2 in said second chamber by applying axial pressure to said vial means so that said needle sequentially pierces said end diaphragm and said intermediate diaphragm and vhereby said ingredients may be dispersed by advancing said plunger toward said intermediate diaphragm·

2. · A two-chamber mixing syringe according to claim 1, wherein said coacting parts lock the isttrermedlate diaphragm against movement in both directions.

3. * A two-chamber mixing syringe according to claim 2, wherein said needle means includes another pointed end projecting from said holder in axial alignment with the pointed end within said space and in fluid communication therewith*

4. * A two-chamber mixing syringe according to claim 2, wherein said needle means has an opening therein spaced from said pointed end*

5. * A two-chamber mixing syringe according to claim k, wherein said intermediate diaphragm and said end diaphragm have axially aligned plerceable portions.

6. A two-chamber mixing syringe according to claim 5» wherein the axial longitudinal extent of said needle opening exceeds the thickness of the plerceable portion of said intermediate diaphragm*

7. * A two-chamber mixing syringe according to claim 6, wherein the needle means within said space projects from end abutment means ex ending from the closed end of said bore* Appln. 46017/2 8, A two-chamber mixing syringe according to claim 7 wherein the abutment means is adapted to be received within said other end of said vial means. 9, A two-chamber mixing syringe according to claim 7» wherein the distance between the abutment means and the opening in the needle does not substantially exceed the thickness of said end dlaphjtagn 10, A two-chamber mixing syringe according to claim 7t wherein the distance between said abutment means and the pointed end of the needle exceeds the combdLned axial extents of the thickness of said end diaphragm, the second chamber and the pierceable portion of said intermediate diaphragm* 11» A two-chamber mixing syringe according to claim 2, wherein portions of the intermediate and end diaphragms defining said second chamber are complementary surfaces for mating engagement* 12» A two-chamber mixing syringe according to claim 2, wherein portions of said plunger and said intermediate diaphragm defining said first chamber are complementary surfaces for mating engagement. 13· A two-chamber mixing syringe according to claim k, wherein said opening is covered by a flexible sleeve which surrounds said needle* Ik, A two-chamber mixing syringe according to claim 2, wherein said coactlng parts include an Inwardly extending circumferential rib in the vial means which cooperate with a circumferential recess in said lntermeftate diaphragm. Appln. 46017/2 15· A two-chamber mixing syringe according to claim lk, wherein a circumferential groove in the exterior sidewall of the vial means provides said inwardly extending circumferential rib and wherein a wire clip having prongs directed toward said one end encircles said groove* 16· A two-chamber mixing syringe according to claim 2, wherein energy storing means is provided between said end diaphragm and the closed end of said bore and is adapted to apply increasing amounts of pressure to said end diaphragm as said axial pressure is applied.whereby said energy storing means drives said end diaphragm toward said intermediate diaphragm when said needle pierces said intermediate diaphragm. 17· A two-chamber mixing syringe according to claim 16, wherein said energy storing means comprised a spring* 1

8. A two-chamber mixing syringe according to claim l f wherein said needle has a beveled edge, the axial extent of which exceeds the axial extent of a plerceable portion of said Intermediate diaphragm* 19· A two-chamber mixing syringe according to claim 3, wherein filter means is provided between the pointed ends of said needle means* 20· A two-chamber mixing syringe according to claim 1, wherein there is provided means between said vial and said cup-shaped holder to prevent withdrawal of said vial from said holder prior to and during axial movement of said vial and cup-shaped holder relative to each other. 21. A two-chamber mixing syringe according to claim 20. wherein said means for preventing said axial movement is located in a circumferential groove in the exterior sidewall Appln. 46017/2 22· A two-chamber mixing syringe according to claim 9» wherein the needle has a beveled edge which constitutes said window opening* 23· A two-chamber mixing syringe comprising: a* a glass cylinder; b. a plunger slidable within and closing one end of the cylinderi c* an end diaphragm closing the other end of the cylinder; d. a stationary intermediate diaphragm within said cylinder separating the interior of the cylinder into first and second chambers respectively defined by said plunger and intermediate diaphragm and by said intermediate diaphragm and end diaphragm; cylinder and said/intermediate diaphragm having coacting parts that comprise means for locking the intermediate diaphragm against axial movement toward said plunger during a mixing and during a dispensing operation; said coacting parts comprising radially extending interengaging and interfering surfaces on said vial means and said intermediate diaphragm; e« a cup-shaped holder having a cylindrical bore closed at one end and receiving said other end of said with said other end of said cylinder cylinder/spaced from said olosed end of said bore; and f· a hollow pointed needle within the space between said other end of said cylinder and said closed end of said bore* whereby an ingredient in said first chamber may be mixed with an ingredient in said second chamber by applying axial pressure to said 1 \ Appin. 46017/2 vial means so that said needle sequentially pierces said end diaphragm and said intermediate diaphragm and whereby said ingredients may be dispersed by advancing said plunger toward said intermediate diaphragm* 2k· A two-chamber mixing syringe according to claim 23, wherein said coacting parts lock said intermediate diaphragm against axial movement toward said plunger and intermediate diaphragm. 25· A two-chamber mixing syringe according to claim 24, wherein said coacting parts comprise an inwardly extending circumferential rib in the cylinder which cooperates with a circumferential recess in said Intermediate diaphragm* Tel-Aviv, November 6, 1 7 .