SAFETY DEVICE FOR MEDICAL SYRINGE

Abstract: A medical Disposable Syringe for personnel protection against needlestick injury having two added parts: 1) protective sleeve (2) adapted to cover the needle (4) after use; adaptor (3, 30) to be coupled to syringe tip (9) and provided with locking means (24, 31, 41) capable of locking the needle (4) to said adaptor (3, 30). The invention allows safe cover of the needle (4) and safe removal of needle after use.

Description: SAFETY DEVICE FOR MEDICAL SYRINGE Field of the Invention The present invention relates, in general, to a safety device for medical syringe for injecting a medical fluid into a patient or for withdrawing a body fluid from same. In particular, the invention relates to a medical syringe provided with protection means against needlestick injury while handling the syringe and allowing safe removal of needle from syringe. Background of the Invention It is well known that health care workers are sometimes injured when in contact with the tip of the syringe needle. Generally, this may not have serious effects, but in some cases, where the patient's body fluids bear contagious elements, such contagious elements may be passed on from the injected patient to the syringe handler. The danger health care workers, including doctors, nurses, laboratory and housekeeping personnel are exposed to, has significantly increased in the last years due to the easy transfer of AIDS virus, as well as commonly known contagious deseases, such as Acute Viral Hepatitis. G reat effort has been invested in protecting medical personnel against possible injury while handling syringes. Furthermore, efforts are invested in safe disposal of used needles, so as to prevent drug users, or any other unauthorized persons, from using needles, which might be contaminated. Thus, it is now a common rule in medical centers to discard used needles for destruction. Used needles are inserted into protective containers for disposal purposes just after completing use of same. Yet, it is well known that many injuries occur to medical personnel while removing the needle from the syringe for disposal purposes. Various kinds of syringe needle covers have been sugges¬ ted in order to diminish risk to the user who has any direct contact with the tip of the needle. Thus, U.K. Patent Application No. 2,208,604 discloses a medical syringe having a protective sleeve capable of fitting over the used needle when the latter is coupled with the syringe and of making a snap-locking engagement with the syringe barrel when the needle is enclosed in the sleeve. The rigid cover disclosed is fixedly secu¬ red in position and cannot be removed without breaking the syringe, therefore eliminating its use for blood withdrawal from patient. It is well known that for most blood tests it is prohibited to use the needle for the transfer of blood from syringe to test tube and, therefore, removal of needle is required prior to transfer of blood samples from syringe to testing containers. Therefore, the syringe assembly disclosed in above mentioned U.K. patent specification cannot serve for withdrawal of body fluids from patients, wherein emptying the syringe should be carried out after the removal of the needle. U.K. Patent Application No. 2,225,723 discloses a new needle assembly and cylindrical cover housing which are usable with conventional syringes. The needle assembly is especially constructed with catch slots to be adapted to receive inward projections in cover housing for engagement thereof, so as to secure the needle assembly in the cover housing after usage. However, the device disclosed does not have means for the detachment of needle, when required. Brief Description of the Invention It is the object of the present invention to provide for simple safety means for the removal of injection needle from syringe. It is a further object of the present invention to provide for simple operable means for covering the needle of a syringe immediately after withdrawal of same from a patient, during subsequent handling and while removing the needle from the syringe. In accordance with the present invention, . there is provided a syringe adapted to be coupled to a needle, said syringe having a protective sleeve adapted to cover said needle after use and to remove same from said syringe thereafter, while the needle is protected by said sleeve comprising : a known syringe having a substantially cylindrical hollow barrel with a tip adapted to be coupled to a known sterilized needle and provided with a plunger; adaptor means adapted to be coupled to said tip and to said needle; a substantially cylindrical sleeve located around said barrel provided with stopping means structured in corre¬ lation with the size and structure of said adaptor; wherein said sleeve is capable of fitting over said needle when pulled longitudinally along said barrel, until stopped by said stopping means and wherein subsequent longitudinal pull of the sleeve results in detachment of said adaptor together with needle and sleeve from said known syringe. The invention also provides for an adaptor, adapted to be coupled to known syringe and known needles. The adaptor of the invention is a substantially hollow cylinder characterized in that its outer diamete ' r being slightly bigger than the outer diameter of the hollow barrel and slightly smaller, or equal to the inner diameter of the protective sleeve. The adaptor of the invention is provided with locking means capable of locking the needle to the adaptor, allowing the adaptor to pull the needle from the tip of the syringe, when the stopping means of the sleeve are pushed against the adaptor, thereby detaching the cove¬ red needle together with the adaptor fron the syringe. It should be noted that known disposable needle are commonly provided with connical plastic base adapted to be coupled to the tip of a syringe. The plastic conical base of the needle is provided with rims at its bottom. Preferably, the adaptor of the invention is structured to have an inner contour provided with protrusions, grooves or the like, adapted to be attached to the plastic base of known needles. The inner contour may be provided with spiral protrusion or other known means capable of locking the plastic rims of the needle base. Alternatively, the adaptor of the invention may be provided with any other known attachment means for the connical base of the needle, such as a hollow connical extension of the adaptor, dimensions of which are to be coupled to the inside of the plastic base of the needle such as by frictional force, thereby providing locking means for the needle. The adaptor of the invention may be attached to the known syringe by attachment means associated with the structure of the syringe. The adaptor may be coupled to the known syringe to form the syringe of the invention, after the needle connected to the adaptor is attached to the tip of the barrel. Preferably, the stopping means of the protective sleeve of the invention are located at the inner surface of the sleeve towards the end of the sleeve, remotest of needle. The invention also extends to an adaptor forming an integral part with the needle, preferably with the connical base of the needle, provided that the dimensions of the adaptor are such that its outer diameter is slightly bigger than the outer diameter of the hollow barrel of the known syringe it is to be attached to, and is slightly smaller or equal to the inner diameter of the protective sleeve provided with the known syringe. The protective sleeve of the invention may be slightly slanted, the inner diameter of the sleeve slightly de¬ creasing as the sleeve is pulled over the barrel and the adaptor, for the covering of the needle. The smallest inner diameter of the sleeve being substantially equal to the outer diameter of the adaptor and located towards the end of the sleeve, thereby forming a tight friction¬ al contact with the adaptor. Thus, the fact that said diameter of sleeve is equal to the outer diameter of the adaptor, serves as the stopping means of the sleeve. Alternatively, the stopping means of the sleeve may be any protrusion or groove at .the inner surface of the sleeve, which stops the sleeve from beinc; further pulled over the adaptor. Preferably, all components of the syringe of the invention are made of disposable materials such as plastic materials. Preferably, the adaptor of the invention is made of rigid materials, though flexible materials may also be used, or a combination thereof. Preferably, the protective sleeve and other components of the syringe of the invention are made of transparent material. Brief Description of the Drawings The invention is illustrated in more details by way of example only, with reference to the accompanying drawings in which : Figure 1 is a side view of a syringe according to the invention, having a covered needle coupled therewith prior to use. Figure 2 is an exploded view of the syringe with covered needle shown in figure 1. Figure 3 is a crossectional ' view of an adaptor according to the invention. Figure 4 is a crossectional view of another embodiment of an adaptor according to the invention. Figure 5 is a side view of the syringe shown in figure 1 immediately after withdrawal of needle from patient. Figure 6 is a side view of a following position of the syringe of figure 5 with covered needle. Figure 7 is a side view of a following position of the syringe of figure 6 with detached needle. Detailed Description of the Invention Syringe 100 with needle shown in figures l and 2 comprises five basic units; syringe 1, protective sleeve 2, adaptor 3, needle 4 and needle cover 5. Syringe 1 comprises cylindrical hollow barrel 6 having rims 8 tangential thereto, plunger 7, with rod 20 attached thereto and tip 9 adapted to be coupled to needle 4 in any known manner. It should be noted that syringe 1 is a known syringe unit of common use. It should be also noted that the outer walls 10 of barrel 6 are slightly slanted as dictated by the method of manu¬ facturing plastic syringe. Thus, the circumference of barrel 6 is gradually increasing along its main axis to¬ wards rims 8. Sleeve 2 is a hollow cylinder with sligh¬ tly slanted walls the slope thereof being in opposite direction to the slope of the outer walls 10 of hollow barrel 6. Sleeve 2 is also provided with a tiny inner step 22 adjacent to the narrowest end of sleeve 2. The lowest inner diameter of sleeve 2 marked in figure 2 by letter d serves as the stopping means of the sleeve and as detachment means in association with the structure of the adaptor as will be explained below. It should be noted that the stopping means of sleeve 2 actually comp¬ rises two means, i.e. the gradual decrease of inner dia¬ meter of sleeve and the further decrease in diameter, resulting from the presence of step 22. It should be emphasized that, in other embodiments of the invention, one of the stopping means described above should suffice as well as any other known stopping means. Needle 4 has a conical plastic base 11 adapted to be mounted on tip 9. Base 11 has a circurlar outward protrusion 12 at its bottom. It should be noted that needle 4, combined with base 11, is a known disposable sterile needle commonly used. Circular adaptor 3 is a hollow cylinder having an alternating outer diameter and inner contour adapted to be coupled to syringe 1 and needle base 11. Adaptor 3 is placed between and partly around tip 9 of syringe 1 and base 11 of needle 4 and is also embracing the end of hollow barrel 6 adjacent to tip 9. The inner surface area of the adaptor adjacent to needle base 11 has spiral protrusions 24 serving as locking means for needle 4, whereby protrusion 12 is screwed into spiral protrusions 24. The inner diameter 26 of adaptor 3 adjacent to hollow barrel 6 is equal to the outer diameter 27 of hollow barrel 6 at its end adjacent to tip 9, thereby allowing attachment of adaptor 3 to syringe 1 by frictional force. Adaptor 3 is also provided with a round inner opening 25, diameter of which is substantially equal to outer diameter of tip 9, allowing to catch adaptor 3 on tip 9 by frictional force. Similar characteristics of the adaptor can also be seen in other embodiments of adaptors shown in figures 3 and 4. Adaptor 30 and 40 shown in figures 3 and 4 are hollow cylinders with external and internal curves different from those of adaptor 3 but having similar characteristic, i.e. means for coupling to needle in the form of spiral protrusions 31 and 41 respectively and external diameter 32 and 42 respectively slightly bigger than the external diameter of hollow barrel 6 and slightly smaller or equal to the lower most inner diame¬ ter (not shown in figures 3 and 4) of protective sleeve 2. The length of adaptor may vary, as can be seen in the various adaptors shown in figures 2 to 4. Adaptor for concentric syringe as shown in figures 2 and 3 are constructed symmetrically whereas adaptor for excentric syringes are non-symetric as shown in figure 4. The most remarkable feature of adaptor 3, allowing the sliding of sleeve.2 to cover and detach needle 4 from syringe 1, as will be explained hereinbelow, is the outer dimension of adaptor 3, having a diameter 28 slightly larger than the inner diameter d of sleeve 2. Thus, the stopping means of the invention serve also as detachment means, allowing to detach needle .4 when covered by sleeve 2 together with adaptor 3 by subsequent longitudinal pull of sleeve 2 whereby the stopping means detach the adaptor from syringe 1, not allowing the adaptor and needle to move forward in the sleeve. In figure 1 syringe 100 is shown prior to use. Syringe barrel 6 is slidably mounted in protective sleeve 2; syringe tip 9 is coaxially mounted in adaptor 3. Covered needle 4 is attached to tip 9 of syringe 1 by a connical base 11 mounted thereon, while adaptor 3 does not obstruct the attachment. Needle cover 5, which is a commonly used cover, is removed just prior to use of syringe, i.e. prior to withdrawing blood from patient, or injecting fluid medicine. Following the removal of the needle from patient, the syringe assumes the position shown in figure 5 wherein plunger 7 together with rod 20 may be positioned in any position along barrel 6 according to the function the syringe was used for, i.e. withdrawal of body fluids or injection of medicine. The arrow in figure 5 shows the direction of longitudinal movement of sleeve 2 along hollow barrel 6. Sleeve 2, having the slight connical structure as mentioned above, can slide relatively smoothly along barrel 6 and adaptor 3, the inner surface area of sleeve 2 touching the outer surface of barrel 6 and adaptor 3, up to the position shown in figure 6, wherein the lowermost inner diameter d of sleeve 2 reaches adaptor 3 and is stopped by step 22. Sleeve 2 thus covers needle 4 and protects the handler of the syringe from accidental pricking. Upon further excertion of force on sleeve 2 in the direction showed by arrow in figure 6, the narrow end of sleeve 2 pushes adaptor 3 away from syringe tip 9, thereby detaching needle 4, protected by sleeve 2, from syringe 1. The friction between the narrow end of sleeve 2 and the outer contour of adaptor 3 not allowing the adaptor and needle to move forward in the sleeve subsequent to the detachment. The protected needle may be disposed at this stage, while the content of syringe 1, when containing blood or any other body fluid is emptied into test tubes or any other containers, as required.

Claims: CLAIMS 1. A syringe adapted to be coupled to a needle, said syringe having a protective sleeve adapted to cover said needle after use and to remove same from said syringe thereafter, while the needle is protected by said sleeve comprising : a known syringe having a substantially cylindrical hollow barrel with a tip adapted to be coupled to a known sterilized needle and provided with a plunger; adaptor means adapted to be coupled to said tip and to said needle and provided with locking means capable of locking the needle to said adaptor; a substantially cylindrical sleeve located around said barrel provided with stopping means structured in correlation with the size and structure of said adaptor; wherein said sleeve is capable of fitting over said needle when pulled longitudina3.1y along said barrel until stopped by said stopping means and wherein subsequent longitudinal pull of the sleeve pushes said stopping means against the adaptor resulting in detachment of said adaptor together with needle and sleeve from said known syringe, not allowing the adaptor and needle to move forward in said sleeve. 2. A substantially hollow cylinder adaptor, adapted to be coupled to known injection needle and known syringe, said syringe being covered by a substantially cylindrical protection sleeve capable of covering said needle, characterized in that the outer diameter of said adaptor is slightly bigger than the outer diameter of the hollow barrel of said known syringe, slightly smaller or equal to the inner diameter of the protection sleeve. 3. An adaptor according to claim 2 having locking means capable of locking the needle to the adaptor. 4. An adaptor according to claim 3 wherein the locking means of the adaptor are located in the inner surface area of the adaptor. 5. An adaptor according to claims 3 and 4 wherein the locking means are spiral protrusions in the inner contour of the adaptor capable of locking the rims of the connical base of known needles. 6. A syringe according to claim 1 having an adaptor as defined by claims 2 to 5. 7. A syringe according to claims 1 and 6 wherein the stopping means of the protection sleeve are located in the inner surface of said sleeve towards the end of the sleeve far off the needle. 8. A syringe according to claims 1, 6 and 7 wherein the stopping means of the protection sleeve is a circumferential step located in the inner surface of said sleeve toward the end of the sleeve far off the needle, the inner diameter of said step being smaller than the outer diameter of the adaptor. 9. A syringe according to claims 1, 6 and 7 wherein the protection sleeve is slightly slanted, the inner diameter of the sleeve decreasing towards the end of the sleeve far off the needle, thereby forming stopping means when the inner diameter of the sleeve, being equal and slightly smaller than the outer diameter of the adaptor, reaches the adaptor upon the longitudinal pull of sleeve along the hollow barrel of the syringe and subsequent longitudinal pull of the sleeve results in detachment of the adaptor, together with the needle and sleeve from the known syringe. 10. An adaptor according to claims 2 to 5 forming an integral part with the needle, whereby the outer diameter of the adaptor is slightly bigger than the outer diameter of the hollow barrel of the syringe to which it is to be attached and slightly smaller or equal to the inner diameter of the protection sleeve. 11. A syringe according to claim 1 substantially as described in the specification with reference to the drawings. 12. An adaptor according to claim 2 substantially as described in the specification with reference to the drawings.

Inventors: GOTTHELF ARTURO MOISES, JESHURUN ELIMELECH, GOTTHELF, ARTURO, MOISES, JESHURUN, ELIMELECH
Applicants: GOTTHELF ARTURO MOISES, JESHURUN ELIMELECH, GOTTHELF, ARTURO, MOISES, JESHURUN, ELIMELECH
Application year: 1992
Main classification: A61M5
IPC codes: A61M5