Dual-chamber Liquid Ejector And Filling Connector

Abstract

A dual-chamber liquid-injecting device includes a powder loaded piston-type syringe attached to a liquid container by a connecting member. The connecting member has an inner sleeve sliding within an outer sleeve with opposite ends of the sleeves coupling the neck of the container to the nozzle of the syringe. Ports on the inner sleeve are sealed within the outer sleeve in a preliminary extended position, and they are opened when the sleeves are pushed together or contracted to communicate the syringe with the container. The contents of the container are then drawn into the syringe. The connecting member is screwed to the neck of the container and attached to the nozzle of the syringe by a snap-fit connection on the inner sleeve. This facilitates ready detachment of the syringe from the connecting member and container for application. Locating stops for the different positions of the sleeves are provided by annular ridges between the sleeves or a cap on an internal boss within the outer sleeve, which also acts as a seal. The cap is automatically pushed off into the container when the connector is pushed together.

Description

BACKGROUND OF THE INVENTION

This invention relates to a dual-chamber liquid ejector or injector, especially for veterinary purposes, including a piston-type syringe which constitutes a first chamber for a substance to be mixed.

In human and veterinary medicine, various devices are needed for administration and injection of drugs. The invention aims at facilitating the administration or injection for the doctor, particularly where the drug to be applied must be mixed from two or more original substances before use. Syringes of various types are known, which provide two chambers containing the original substances to be mixed. When activating the syringe, a partition wall between these chambers is opened, the contents thus becoming ready for use. These previously known dual-chamber syringes are, however, expensive to manufacture or cause difficulties during field use, thus preventing widespread use. Especially in veterinary medicine, devices for administration and injection are needed, which can be handled easily and which may be mass produced at low cost.

For treatment of local disorders in animals, especially in the cow udder, preparations are used wherein the active substances are dispersed in a base containing mineral or vegetable oil. These dispersions are supplied in plastic injectors as ready-to-use syringes, thus permitting direct administration of the drug dispersion into the udder. These drugs, effective in themselves, show disadvantages, because relatively large quantities of the vehicle, consisting of mineral and vegetable oil and thickened with aluminum stearate, must be administered, resulting in delayed release and absorption of the active substance and a possible foreign body reaction in the udder. Moreover, the volume administered is limited by the oleaginous vehicle. In many cases there is not enough fluid available in the udder itself to extract the active substances from the oleaginous vehicle.

For this reason, mineral and vegetable oil preparations have not obtained full market acceptance. Many udder inflammations are therefore treated with aqueous drug solutions. Such preparations are generally marketed in the form of conventional ampuls or vials. One vial contains the active substances in dry form, while the solvent is contained in another vial or ampule. Thus, before treatment, both substances must be drawn into a syringe and the resulting solution of the two substances constitutes the medicament to be administered. The use of such syringes is particularly complicated when several ampuls are administered, especially under the conditions in which veterinary treatments are often performed.

It, therefore, appears advisable to provide aqueous solutions for veterinary application in a two-component syringe, in which they are mixed immediately before treatment in the manner already known in human medicine, e.g., in chloramphenicol injection. Those syringes already known are however, unsuitable for veterinary use as mass-produced articles. There is also a need for a simple and economical connector for rapidly and conveniently filling a liquid injector from a sealed container.

SUMMARY OF THE INVENTION

The present invention aims at creating a dual-chamber injector, especially for veterinary purposes. which may be mass-produced at a low cost and which allows for especially simple handling. The starting point of the invention is an injector in the form of a piston-type syringe, which constitutes a first chamber for a substance to be mixed. A second chamber for a further substance to be mixed is provided by an additional receptacle adapted to be fitted on the nozzle portion of the injector. In the region of the neck portion on the additional receptacle a seal is provided which may be opened by a slidable sleeve. The slidable sleeve is mounted in a connecting member which is connectable with said neck portion and the end of the slidable sleeve remote from the seal provides a seal on the nozzle portion. Such a dual-chamber injector comprises a piston-type syringe with a fitted additional receptacle. The stability of active substances and additives in the individual chambers is maintained by the perfect sealing of the injector from the additional receptacle under sterile conditions. To prepare the dual-chamber injector for use, it is only necessary to slide the additional receptacle with the connecting member in the direction of the injector. This opens the seal or removes or ruptures any additional sealing element. Subsequently, the contents of the additional receptacle enters the slidable sleeve, which surrounds and seals the nozzle portion, and from there it is drawn up into the injector. The additional receptacle with connecting member and the slidable sleeve is then taken off the nozzle portion of the injector. The mixture, which has formed in the chamber of the injector, is ready for use. The connecting member is also useful for rapidly and conveniently filling a liquid injector from a sealed receptacle or container for the liquid.

The connecting member may be designed to permit a combination of additional receptacles with injectors of different sizes, without simultaneously requiring a change of the connecting member and the slidable sleeve. A considerable simplification of assembly is thereby achieved.

The connecting member may advantageously be screwed on the check portion of the additional receptacle with a threaded outer sleeve, and a sealing element or cap and/or ridge may be provided in the region of this threaded sleeve on an internal boss within the connecting member. A central bore of the outer sleeve acts as a guiding element for slidable sleeve. The outer sleeve may also be provided with a socket at the end adjacent the injector, which is adapted to the external shape of the slidable sleeve. When readying the injector for use the sealing element limits the extent of engagement of the sleeve members towards each other. This permits especially convenient handling. Cooperatively arranged annular ridges on the slidable sleeves may permit assembly of the sleeves without contracting them.

The sealing element, provided if necessary in case of stringent sealing requirements, may be designed in different ways depending on the substances to be contained, e.g., as a cap, which may be slipped off, a partition wall capable of being perforated or a sealing ring or ridge between the outer and the inner sleeve. In many cases, an adequate seal is provided by the fit between the outer sleeve and the slidable inner sleeve, whose flow-through recesses communicate with the inside of the additional receptacle only after shifting the slidable inner sleeve into the position for use. In this case, it may under certain circumstances be appropriate to increase the reliability of the seal by providing a seal in the zone of the central bore of the connecting member, opposing the slidable sleeve. It may be advantageous that this seal is designed as a circular lip or ridge, integral with the connecting member.

The slidable inner sleeve may be closed at the end remote from the injector and be provided with an annular end piece at the face side, while the flow-through recesses for the contents of the additional receptacle are provided adjacent the closed end, perpendicular to the longitudinal axis.

The dual-chamber injector, consisting of injector, slidable connecting member, and additional receptacle, may be preassembled as one unit, ready for use. The individual parts of the dual-chamber injector are preferably produced as molded parts, for instance as plastic injection molded parts.

The additional receptacle either contains a sufficient quantity of air or is sufficiently flexible due to material and wall thickness, to allow for changes in volume.

BRIEF DESCRIPTION OF THE DRAWING

Novel features and advantages of the present invention will become apparent to one skilled in the art from a reading of the following description in conjunction with the accompanying drawings wherein similar reference characters refer to similar parts and in which:

FIG. 1 is a side view in elevation of a dual-chamber injector which is one embodiment of this invention assembled with chambers isolated from each other;

FIG. 2 is a left end view of the embodiment shown in FIG. 1;

FIG. 3 is a side view in elevation similar to FIG. 1, partially broken away in cross section;

FIG. 4 is a cross-sectional side view in elevation of the embodiment shown in FIG. 1 in the contracted condition with chambers in communication with each other;

FIG. 5 is a cross-sectional view similar to FIG. 4 in which the contents of the container are drawn into the syringe;

FIG. 6 is a cross-sectional view taken through FIG. 3 along the line 6--6; and

FIG. 7 is a cross-sectional side view in elevation of the connecting portion of another embodiment of this invention.

FIGS. 1 to 6 show a dual-chamber injector 20, incorporating ejector 1 comprising a piston-type syringe. An additional container 4 is connected with the ejector by inner sleeve member 3, slidable in outer sleeve 2. Sleeves 2 and 3 are included within connector 30. In barrel 5 of ejector 1, a shiftable piston 6 is inserted in conventional manner. On barrel 5, there is a nozzle portion 7, which merges into a conical needle portion 8. The end of slidable inner sleeve 3 adjacent to ejector 1 is fitted onto the nozzle portion 7 over circular sealing ridge 22. Flow-through apertures 9 extend through sleeve member 3, transversely or perpendicularly to the longitudinal axis. The end of the slidable sleeve 3 adjacent to the additional receptacle 4 has a circular end base 10 and an annular end 11 which fits snugly against circular lip 24 extending within longitudinal passageway 19 in outer sleeve 2. A tight seal is thereby obtained, despite variation in the diameters of recess 19 and pipe member 3 encountered in production. Another circular lip 28 on inner sleeve 3 also helps guide and seal as later described.

Outer sleeve 2 has a threaded sleeve portion 14 provided with an internal thread whereby it may be screwed onto a correspondingly threaded zone on neck portion 15 of additional receptacle or container 4. Outer sleeve 2 contains a partly conical socket 17, defined by longitudinal ribs 16. The conical recess conforms to the external shape of the end piece on inner sleeve 3. Inner sleeve 3 also has an annular flange 18 on the end coupled to nozzle 7 and is mounted in a central passageway 19 through outer sleeve 2.

Injector 1 has a first chamber I, while a second chamber II is provided by the internal space of the additional receptacle or container 4. In both chambers, respective components of the drug, to be applied as a mixture, may be stored. Powder 21 is thus stored in chamber I and liquid 23 in chamber II.

The dual-chamber injector is assembled and delivered in the position shown in FIGS. 1-3. To ready the injector for use, outer sleeve 2 of connector 30 together with the screwed-on additional receptacle 4 is shifted toward nozzle portion 7 of injector 1 (as shown in FIG. 4) in such a manner that the end portion of inner slidable sleeve 3 adjacent the injector is in contact with recessed ends 17 of radial ribs 16 of the outer sleeve 2. In this case, the end of the inner slidable sleeve 3 adjacent additional receptacle 4 enters the inside of additional receptacle 4. Flow-through apertures 9 then move out of their sealing contact on the inner surface of the central recess 19 of the outer sleeve 2 and now communicate with the interior of the additional receptacle 4. The piston 6 of the injector 1 is then withdrawn (as shown in FIG. 5) thus drawing in the liquid contents of the additional receptacle 4 from chamber II. If desired, the distribution of dry substance or powder 21 and liquid 23 may be reversed. The liquid contents mix with the contents of chamber I, so that the drug is ready for use. The additional receptacle 4 together with the connecting member 2 and the slidable sleeve 3 may then be removed. The injector is then ready for use.

In accordance with the invention, a dual-chamber injector, capable of being assembled ready for use, may be produced, preferably for veterinary medicine, but in special cases also for human medicine. Furthermore, the conical shoulder portion or nozzle 7 of the injector can be advantageously constructed for fitting known injection needles.

FIG. 7 shows the connecting portion 30A of another embodiment of this invention. FIG. 7 shows the parts in the preliminary sealed condition similar to FIG. 3. Cap 13 is mounted on reduced annular end 12A of boss 32A forming an extension of longitudinal passageway 19A within outer sleeve 2A. Cap 13A provides a positive seal between the interior of inner sleeve 3A and chamber IIA in container 4A. Cap 13A also provides a locating stop for the annular end 11A of inner sleeve 3A. When outer sleeve 3A is moved toward the coupling end flange 18A of inner sleeve 3A, annular end 11A of inner sleeve 3A pushes cap 13A off extended annular end 12A of boss 32A into chamber IIA of container 4A. A cap such as 13A may also be used in conjunction with the embodiment shown in FIGS. 1-6 and would therein be positioned on annular extension 11 of boss 32 within the coupling end of outer sleeve 2.

Because of low production costs, such dual-chamber injectors or ejectors are--apart from application in the field of medicine-- also practicable for other fields where a mixture of two separately stored substances is to be produced before use. For example, a similar ejector may be produced as a spraying device for cream, wherein a freeze-dried storable initial product is contained in chamber I and a quantity of liquid required for dissolution in chamber II. Connector 30 may also be used for filling an empty injector 20 with a liquid from a container or receptacle 4. The liquid may thus be maintained sealed in the container until immediately prior to use.

Claims

We claim:

1. A dual-chamber liquid ejecting device comprising a piston-type syringe incorporating a first chamber and a nozzle, a container incorporating a second chamber and a neck, a connecting member including an inner sleeve movably inserted within an outer sleeve, coupling means on the opposite ends of said sleeves connecting said outer sleeve to said neck of said container and said inner sleeve to said nozzle of said syringe, port means on a portion of said inner sleeve insertable within said outer sleeve, and sealing surface means in said outer sleeve for closing said port means in one relative position of said inner and outer sleeves and for permitting said port means to communicate with said neck coupling means in another relative position of said inner and outer sleeves whereby the contents of said second chamber may be drawn into said first chamber through said inner sleeve and said nozzle.

2. A device as set forth in claim 1 wherein radial guide vanes are disposed within said outer sleeve in an array adjacent and about said inner sleeve for maintaining said sleeves longitudinally aligned.

3. A device as set forth in claim 2, wherein the coupling end of said inner sleeve and the adjacent ends of said radial guide vanes are mutually conically shaped for engaging nesting contact with each other.

4. A device as set forth in claim 1 wherein said inner and outer sleeves include mutually contacting longitudinal walls, said port means comprises aperture means in said longitudinal wall of said inner sleeve, said inner and outer sleeves slide longitudinally relative to each other, and said sealing surface means comprises said longitudinal wall in said outer sleeve within which said inner sleeve slides, said coupling end of said inner sleeve being longitudinally displaced away from said coupling end of said outer sleeve in said one relative position whereby said aperture means are maintained in sealing contact within said longitudinal wall in said outer sleeve, and said sleeves being longitudinally contracted in said other relative position of said sleeves whereby said aperture means moves out of contact with said longitudinal wall in said outer sleeve into communication with said neck coupling means on said outer sleeve.

5. A device as set forth in claim 4 wherein said outer sleeve includes a cylindrical boss extending the longitudinal cylindrical wall of said outer sleeve within which said inner sleeve slides toward said neck coupling means, and cap means being detachably mounted upon said cylindrical boss to help seal said inner sleeve from said neck coupling means.

6. A device as set forth in claim 4 wherein said neck coupling means comprises threaded connecting means on said neck and within the end of said outer sleeve.

7. A device as set forth in claim 6, wherein said coupling means also includes a snap-fitting means on said nozzle and within said coupling end of said inner sleeve.

8. A device as set forth in claim 4 wherein annular ridge means is disposed within said outer sleeve in contact with said inner sleeve to help seal the space therebetween.

9. A device as set forth in claim 8 wherein annular ridge means is also provided on said inner sleeve means in contact with said outer sleeve means to help seal the space therebetween.

10. A connecting member for filling a liquid ejector incorporating a first chamber and a nozzle from a container incorporating a second chamber and a neck, said connecting member comprising an inner sleeve inserted to slide within an outer sleeve, coupling means on the opposite ends of said sleeves for connecting said outer sleeve to said neck of said container and said inner sleeve to said nozzle of said liquid ejector port means on a portion of said inner sleeve inserted within said outer sleeve, said inner and outer sleeves include mutually contacting longitudinal walls, said port means comprises aperture means in said longitudinal wall of said inner sleeve, said coupling end of said inner sleeve being longitudinally displaced away from said coupling end of said outer sleeve in a preliminary relative position in which said aperture means is maintained in sealing contact within said longitudinal wall in said outer sleeve, and said sleeves being longitudinally contracted in said other relative position of said sleeves whereby said aperture means moves out of contact with said longitudinal wall in said outer sleeve into communication with said neck coupling means.

11. A connecting member as set forth in claim 10 wherein said outer sleeve comprises a cylindrical boss extending the inner longitudinal cylindrical wall of said outer wall within which said inner sleeve slides toward said coupling means.

12. A connecting member as set forth in claim 11 wherein radial guide vanes are disposed within said outer sleeve in an array adjacent and about said inner sleeve for maintaining said sleeves longitudinally aligned.

13. A connecting member as set forth in claim 12 wherein said neck coupling means comprise internal connecting means within the end of said outer sleeve for connection to the neck of said container and an enlarged end on said inner sleeve for connection to said liquid ejector.

14. A connecting member as set forth in claim 13 wherein circular sealing ridges are disposed between said inner and outer sleeves for sealing the space therebetween.