Syringe

Abstract

A syringe formed of inner and outer tubular members with the inner member adapted to be telescoped within the outer member and sealed therefrom by a sealing assembly comprising a disc member having at least one opening therethrough communicating with the inner tubular member and a flexible seal having a disc portion having openings therethrough, with the openings in the disc member being laterally offset from the opening in the disc portion, while the outer member is formed with a rupturable seal having an injection needle in alignment therewith for rupture in use with the inner tubular member adapted to contain a liquid carrier and the outer tubular member adapted to carry a solid medicant to be taken up with the carrier for injection whereby the materials are freshly mixed immediately prior to injection.

Description

This invention relates to a device for the administration of parenteral solutions and more particularly to a hypodermic syringe adapted to contain dry solids separate and apart from the dissolving or carrier liquids until, immediately prior to administration, the liquid is caused to flow into the compartment containing the solids for injection of the formed mixture.

To the present, it has been the practice to make use of stock solutions housed within a container of relatively large capacity, from which increments can be removed, as desired, for administration by a suitable syringe. This procedure is deemed to be unsatisfactory because most such solutions are of insufficient stability to militate against change before the stock solution has been used up. With a solution of short "shelf life", its utility may become dissipated before the solution has been completely utilized.

The most effective means for maintaining the "shelf life" over extended periods of time is to maintain complete separation between the liquid carrier and the solids to be incorporated therein, until immediately prior to use. Maintenance of solid-liquid separation until time of use presents other problems with respect to ejecting and administering the solution containing the necessary concentration of ingredients and under the most sanitary conditions. The usual practice is to introduce the solids into the liquid for solution in a suitable container from which the solution can be withdrawn into a syringe for injection. This procedure requires the use of at least three separate containers and maintenance under sterile conditions as well as accurate measurement of the ingredients.

In copending application Ser. No. 632,622, filed May 28, 1968 and entitled "Disposable Syringe", description is made of a syringe in which accurately measured amounts of solid medicants and liquid carrier can be maintained in a completely separated state, and can be admixed together and injected, while the contents of the syringe are in a sealed and sanitary condition.

The present invention relates to a further improved syringe of the type described in which use is made of a further simplified and improved closure member between the liquid-containing and solid-containing compartments.

It is an object of the present invention to provide a new and improved syringe which houses both liquids and solids in separately sealed compartments whereby admixture of the liquids and solids can be effected completely within the confines of the syringe in a simple and efficient manner to provide a freshly prepared medicant solution which can be injected in the manner desired for use.

This and other objects and advantages of the invention will appear hereinafter, and, for purposes of illustration, but not of limitation, an embodiment of the invention is shown in the accompanying drawings in which:

FIG. 1 is a sectional elevational view of a syringe embodying the features of the invention, illustrating the position of the elements prior to use;

FIG. 2 is a plane view of a flexible disc member forming part of the closure assembly of the present invention;

FIG. 3 is a plane view of the flexible seal of the closure assembly of the present invention;

FIG. 4 is a sectional elevational view of the syringe shown in FIG. 1 with the syringe partially actuated to effect displacement of the liquid contents from the liquid-containing chamber to the colids-containing chamber for admixture; and,

FIG. 5 is a sectional elevational view of the syringe shown in FIGS. 1 and 2 with the syringe in fully actuated position to effect displacement of the freshly prepared medicant solution from the solids chamber for injection;

FIG. 6 is a sectional elevational view of an actuator which may also be used as a needle cover;

FIG. 7 is a sectional elevational view of the syringe of FIG. 1 having an alternative needle assembly.

The concepts of the present invention reside in a syringe comprising inner and outer tubular members with the inner tubular member adapted to be telescoped within the outer tubular member, a hypodermic needle assembly including a rupturable closure sealing the forward end of the outer tubular member in which the closure is adapted to be ruptured in response to displacement of a needle and a flexible closure assembly sealing the forward end of the inner tubular member including a disc member having one or more openings therethrough communicating with the interior of the inner tubular member and a flexible seal having a substantially flat surface portion in face-to-face sealing contact with the disc member.

The surface portion of the flexible seal is also provided with at least one opening therethrough, which is offset from the opening or openings in the disc member to prevent the passage of a liquid contained in a chamber defined by the inner tubular member. When the interior of the inner tubular member is subjected to an internal pressure during displacement of the liquid from the chamber defined thereby, the liquid passes through the openings in the disc to thereby flex the surface portion of the flexible seal, forming a space between the flexible disc and the flexible seal. Thus, the liquid contained in the chamber defined by the inner tubular member can pass through the openings in the flexible disc member and surface portion of the flexible seal, and through the opening or openings in the flexible seal into the solids-containing chamber defined by the outer tubular member for admixture with the solids to form a fresh medicant solution for injection.

By the same token, an internal pressure in the chamber defined by the outer tubular member, such as that caused during injection, serves to urge the surface portion of the flexible seal toward sealing contact with the disc to prevent flow of liquid through the flexible closure assembly in the reverse direction. In this way once admixture of the liquid with the solid has been made, it is no longer necessary to maintain a pressure in the chamber defined by the inner tubular member, and injection of the freshly prepared solution can be effected by displacing the inner tubular member toward the outer tubular member.

Referring now to the drawings, there is shown in FIG. 1 a syringe embodying the features of the invention comprising an outer casing 10 in the shape of a tubular member formed of glass, plastic or the like having a continuous bore 12 extending therethrough from an open rearward end portion 14 of smaller cross section at the forward end.

The forward end of tubular member 10 is sealed by means of a diaphram or disc member 18 held in place in a sealing relationship across the open neck 16 of tubular member 10 by means of a cap 20 forming part of the needle assembly which is crimped about the outer neck portion of the tubular member, while the inner portions 22 of cap 20 overlap the outer edge of the disc member 18 overlying annular flange 24 to tubular member 10. The rearward end of tubular member 10 is formed with an outwardly extending flange 26 which serves as a finger grip.

The needle assembly comprises the cap 20 which is crimped about annular flange 24, and a hollow needle 28. Needle 28 is carried by a bushing 30 which is slidably mounted in a recess 32 formed by the annular wall 34 of cap 20, and is held in place by inwardly extending flange 36 located on the annular wall 34 of cap 20. Bushing 30 is provided at its rearward end with an outwardly extending flange 38 having a cross section greater than the cross section of flange 36 to prevent the bushing 30 and needle 28 from being released from recess 32. In addition, bushing 30 and needle 28 are spring biased against flange 36 by spring means 40 to maintain sharpened portion 42 of needle 28 which extends rearwardly from bushing 30 adjacent to disc member 18.

A second tubular member 44 formed of glass, plastic or the like material is dimensioned to have an outer wall-to-wall dimension which is less than the inner wall-to-wall dimension of tubular member 10 whereby the second tubular member 44 is adapted to be telescoped through the outer tubular member 10. The second or inner tubular member 44 is similarly formed with a passage 46 extending from an open rearward end 48 through a neck portion 50 at the forward end having a smaller cross section.

The forward neck end portion of the inner tubular member 44 is fitted with flexible sealing member 52 including an outer ribbed portion 54 fitted in a gripping relationship about the neck of inner tubular member 44 and extending laterally beyond the wall of the inner tubular member 44 for a distance to effect sealing engagement with the inner wall of outer tubular member 10 whereby inner tubular member is capable of functioning as a piston which is moveable axially relative to the outer tubular member 10 to thereby provide a piston and cylinder arrangement between the inner and outer tubular members 44 and 10, respectively.

Flexible sealing member 52 is illustrated as having a gripping member 56 which extends inwardly to grip annular flange 58 formed at forward end of inner tubular member 44 to effect the gripping relation described above. Flexible sealing member 52 is also provided with a substantial flat or disc portion 60 having one or more passage means 62 extending therethrough.

Disc portion 60 of flexible sealing member 52 overlays a disc member 64 which in turn overlays annular flange 58 formed at the forward end of inner tubular member 44. Thus, disc member 64 is held in place in abutting relation with flange 58 by means of flexible sealing member 52. Disc member 64, which need not be, but preferably is formed of a flexible material such as rubber, is provided with a plurality of openings 66 therethrough which communicate with the chamber defined by tubular member 44, but which are offset laterally from the opening or openings 62 defined by the disc portion 60. Thus, when there is no internal pressure in the chamber defined by tubular member 44, the openings 66 in disc member 64 are sealed by the disc portion 60 of flexible sealing member 52.

The disc member 64 and flexible sealing member 52 are best illustrated in FIGS. 2 and 3, respectively. As shown in FIG. 2, the openings 66 extending through disc member 64 are spaced about the center of the disc member 64 but are spaced outwardly from axial alignment with passage 46. As shown in FIG. 3, the opening 62 in disc portion 60 is located at the center thereof. Disc member 64 and disc portion 60 are concentric, and thus opening 62 in disc portion 60 overlays the center of disc member 64 in sealing relation therewith. Thus, disc portion 60 of flexible sealing member 52 is flexed for displacement from sealing relation with disc member 64 in response to an internal pressure within the chamber defined by tubular member 44. However, as will be understood by those skilled in the art, openings 62 and 66 can have a variety of other offset positions.

The rearward end portion of the inner tubular member 44 is formed with an outwardly extending flanged portion 68 which similarly serves as a finger grip, as will be hereinafter described. The rearward end of passage 46 is sealed with an elastomeric plug 70 mounted for axial displacement through passage 46 as a piston within the cylinder defined by inner tubular member 44. Means, such as a threaded stud 72, is provided on the rearward end of the plug 70 for connection of an actuator 74 for displacement of the piston 70 relative to the cylinder.

In the drawing, the actuator 74 is in the form of a third elongate tubular member dimensioned to have a cross section less than the cross section of passage 46 through inner tubular member 44 and formed at one end with an internally threaded engagement onto threaded stud 72. The rearward end of actuator 74 is formed with an outwardly extending flange portion 78 for use as a finger grip.

In the modification shown in FIG. 6, actuator 74' is capable of use as a needle cover to protect needle 28 when not in a position ready for use, and which can be removed from the bushing 30 to expose the needle and for attachment to the stud 72 for operation of the device, when in position for use. Thus, this element serves a dual function of a needle protector during non-use and of an actuator in use.

By way of further modification, use can also be made of a needle assembly of the type described in copending application Ser. No. 732,622 as shown in FIG. 7 of the drawings. As illustrated in this figure, the outer tubular member 10' is sealed at neck 16' by means of a diaphragm 18' overlaying flange 24'. Diaphragm 18' is maintained in a sealing position with flange 24' by means of a cap 78 which is crimped about the outer neck portion of tubular member 10' while the inner portion 80 of the cap 78 overlays diaphragm 18'.

A hub member 82 has a skirt portion 84 which is crimped about the skirt portion of the cap for securing the hub onto the neck end portion of tubular member 10'. The hub is also formed with an intermediate collapsible portion 86 extending forwardly in axial alignment with the forward end of tubular member 10' with a hub 88 on the forward end through which a hollow needle 28' extends with a sharpened end portion 42' of needle 28' projecting into the interior of hub member 82 for a distance less than the spaced relationship between the hub end 88 and the diaphragm 18', when in position prior to use, to thereby position the rearward end 42' of the needle 28' immediately in advance of the center of the diaphragm 18'.

In the assembled device as illustrated in FIG. 1, a fluid 90 is housed within the inner tubular member 44, while a solid medicant 92 is housed within tubular member 10. Both chambers are sealed, and therefore the loaded device can be stored and/or shipped for extended periods of time without deterioration of the contents and without exposure of the contents to non-sanitary conditions.

In use, the device can be held with two fingers under flange 68 of the inner tubular member 44, and the actuator 74 is pressed by the thumb to effect displacement of the plug 70 through cylindrical passage 46. This in turn subjects the liquid 90 to pressure. The liquid passes through openings 66 in disc member 64 whereby the pressure transfers to the resilient disc portion 60 of flexible sealing member 52 to cause flexure in disc portion 60 to thereby form a small space 94 defined between disc member 64 and flexed disc portion 60. Thus, liquid contained within tubular member 44 is caused to be displaced under pressure through openings 66 in disc member 64, into space 94 and through disc portion 60 through opening 62 into the outer tubular member 10 in which the liquid 90 is admixed with the solid 92. This intermediate position is illustrated in FIG. 4 of the drawing. The liquid carries the medicant into solution or suspension, with shaking when necessary, to provide a freshly prepared fluid system ready for administration by injection.

Administration of the freshly prepared fluid system can be made without transferring the fluid from one device to another and without exposure by inserting the needle 28 into the vessel or tissue. Thus, the outer casing is grasped with one hand with the needle fingers between the flange 26, and the needle is inserted. In the embodiment shown in FIG. 1, removal of the needle cover releases the spring biased needle and bushing and causes the bushing 30 carrying needle 28 to be displaced rearwardly whereby the rearward end 42 of needle 28 punctures the diaphragm 18 to bring the end of the needle into the chamber defined by tubular member 10 for direct communication with the freshly prepared fluid system.

In the embodiment shown in FIG. 7, insertion of the needle 28' compresses the hub member 86 to effect relative movement between needle 78' and diaphragm 18' whereby the rearward end 42' of needle 28' ruptures diaphragm 18' for direct communication with the liquid system.

Thereafter, the thumb is pressed down on the actuator which, at the end of its travel in tubular member 44, causes displacement of the inner tubular member for movement as a piston through the cylindrical passage 12 to thereby forcibly displace the freshly prepared liquid system from the interior of tubular member 10 through the needle and into the tissue, as shown in FIG. 5. Reverse flow of the liquid system due to a fluid pressure within tubular member 10 back through openings 62 and 66 is prevented by virtue of the fact that fluid pressure within tubular member 10 urges disc portion 60 toward a sealing relation with disc member 64.

Upon administration of the freshly prepared solution, the entire device can be discarded.

It will be apparent from the foregoing that I have provided a simple disposable syringe capable of operation with one hand in which liquids and solids are maintained in separately sealed chambers and mixed immediately prior to injection by a simple operation of the device.

It will be understood that changes may be made in the details of construction, arrangement and operation without departing from the spirit of the invention, especially as defined in the following claims.

Claims

I claim:

1. In a syringe assembly including inner and outer tubular members with the inner tubular member having an outer wall-to-wall dimension less than the inner wall-to-wall dimension of the outer tubular member to enable the inner tubular member to be telescoped within the outer tubular member, a rupturable closure sealing the forward end of the outer tubular member, a hypodermic needle, means supporting said needle to permit said needle to penetrate said rupturable closure in response to insertion of said needle, a piston plug dimensioned to be slidably received within the inner tubular member, and means to actuate the piston plug axially relative to the inner tubular member, the improvement comprising a flexible seal sealing the forward end of the inner tubular member, said seal comprising a piston ring portion on the forward end of the forward end of the inner tubular member in sliding engagement with the inner walls of the outer tubular member and a flexible disc portion having at least one opening therethrough communicating with the outer tubular member, and a disc member having at least one opening therethrough communicating with the inner tubular member, said disc portion overlaying said disc member in a sealing relation on the forward end of the inner tubular member and the opening in said disc member being laterally offset from the opening in said disc portion whereby said disc portion is flexed in response to an internal pressure within said inner tubular member and transmitted through the opening of the disc member to permit the flow of a fluid in the inner tubular member through the openings in said disc member and said disc portion to the outer tubular member.

2. A syringe as defined in claim 1 which includes a removable cover for the needle.

3. A syringe as defined in claim 1 in which the inner tubular member is adapted to contain a liquid carrier and in which the outer tubular member is adapted to contain a dry material to be taken up by the liquid carrier when the latter is forced from the inner tubular member into the outer tubular member in response to movement of the piston plug axially in the inner tubular member.

4. A syringe as defined in claim 1 in which the piston ring portion on the forward end of the inner tubular member comprises ring members of rubber-like material in sealing engagement with the outer walls of the inner tubular member and extending into sealing engagement with the inner walls of the outer tubular member.

5. A syringe as defined in claim 1 wherein said disc member includes a plurality of openings in a position offset outwardly from axial alignment with the passage through the inner tubular member.

6. A syringe as defined in claim 1 wherein the opening through the disc portion is positioned in axial alignment with the passage through the inner tubular member.

7. A syringe as defined in claim 1 which includes means on the rearward end of the piston plug for attachment of an actuator and which includes an elongate actuator dimensioned to exceed the length of travel of the piston plug through the inner tubular member.

8. A syringe as defined in claim 7 in which the actuator comprises an elongate rod dimensioned to be received in telescoping relation within the inner tubular member and with means for attachment of the actuator to the piston plug.

9. A syringe as defined in claim 1 which includes flanged members extending radially outwardly from the rearward end portions of the inner and outer tubular members for use as finger grips.

10. A syringe as defined in claim 1 wherein said means supporting said needle includes a bushing and a cap member secured to the forward end of the outer tubular member and defining a recess, said bushing being slidably positioned in said recess relative to the cap member whereby insertion of the needle displaces the needle to rupture said closure.

11. A syringe as defined in claim 1 wherein said means supporting said needle includes a collapsible hub member secured to the forward end of the outer tubular member, said hub member having a flexible portion to permit displacement of the needle to penetrate said closure in response to insertion of said needle.