hypodermic needle with a protrusion

Abstract: Hypodermic needle (2) to be introduced between the skin (17) and the tissue adjacent to the skin. To separate the skin from the tissue, cartilage or bone (18) below the skin and to prevent the tip (6) of the needle (2) to pierce the tissue below the skin it is proposed to provide the extremity of the needle with a protrusion (4). To prevent damage to the living being in which the needle (2) is introduced the transition of the protrusion (4) to the needle (2) is smooth in all directions. The protrusion (4) is provided on that side of the needle (2) which will be adjacent to the tissue, cartilage or bone (18) of the living being.

Description: The invention relates to an apparatus according to the preamble of claim 1. Such an apparatus is known from FR-A-2 057 353. In this French patent specification the needle is used to be introduced through a stopper. To prevent that material from the stopper enters the needle at its end opposed side walls are pinched together such that two openings result. Through pinching together of opposed side walls a protrusion results between them. This needle is designed to transfer fluids, and the cross section of the needle is decreased, because of pinching together the opposed side walls. From US-A-3 277 893 a hypodermic needle is known having a protrusion functioning as barb. The needle disclosed therein is designed to be shot in animals from a considerable distance. In that case it is important that the needle will remain in the skin of the animal. Normally such a needle is shot perpendicular to the surface of such an animal. In the art hypodermic needles are used to insert solids and fluids, such as transponders, or drugs immediately below the skin and parallel to the skin. To that end an opening is pierced through the skin of the living being by the needle. After that the needle is often tilted such that it is moved parallel to the skin. During this movement it is important that the skin is lifted from the underlying tissue, bone or cartilage. Furthermore it is important that the tip of the needle will not pierce in the tissue below the skin. This means that the operator must be able to find his way below the skin of the living being with the needle without being able to see the tip of the needle. The invention aims to realize a needle which makes it possible to clearly define the path between the lower side of the skin and the upper side of the tissue, cartilage or bone below the skin. It is possible with this needle to transport articles, such as transponders, which are relatively vulnerable and cannot be bent to follow any curvature of the needle. The invention also aims to realize a needlebeing able to inject an article into the tissue of a living animal According to the invention this is realized with the characterizing features of claim 1. With these measures it is possible transfer a transponder through the extremity of the needle and introduce it in an animal. According to a preferred embodiment of the invention near the extremity of the needle pusher means are provided to move absorbed articles, such as a transponder, in the needle. A perfect smooth transition face between the protrusion and the needle will be obtained if the transition between the various parts of the protrusion is circular. To be able to introduce objects or drugs the needle is preferably hollow. According to a further preferred embodiment of the invention the tip of the needle is bevelled and the farthest extremity positioned to be placed remote from the skin of the living being after the introduction of the needle under the skin. The tip of the needle is first used to pierce the skin and after that the needle is tilted and the tip functions to lift the skin from the underlying tissue, cartilage or bone. Although the protrusion can be realized on the outside surface of the needle with all prior art means, according to a preferred embodiment of the invention, the tip of the needle is provided with a depression to realize the protrusion. The invention will be further elucidated referring to a preferred embodiment of the invention shown in the drawing, wherein: Fig. 1 shows in cross section an apparatus provided with the needle according to the invention; and fig. 2 shows the tip of the needle during insertion in a living being. In Fig. 1 an injector 1 is shown comprising a housing 3 and needle 2. The needle 2 is rigidly connected to housing 3 through sleeve 19. Needle 2 is provided near its extremity 6 with a protrusion 4. This protrusion 4 is provided by depressing a part of the wall of needle 6. The outer part of housing 3 is provided with a trigger 12 which can be actuated against a spring 13. Trigger 12 is designed to engage an opening 11 in sleeve 10. Sleeve 10 is provided with a support block 9 in which a pushing rod 7 is mounted. One side of pushing rod 7 is introduced in hollow needle 2 whilst a protruding end of it acts to receive a compression spring 8 which on the other hand engages on housing 3. 14 indicates a product to be introduced in an animal such as a drug or a transponder used for identifying animals. The apparatus shown in fig. 1 functions as follows. In the position shown in fig. 1 spring 8 is under compression. In this condition shown the needle is introduced under the skin of the animal as will be further elucidated with regard to fig. 2. After complete introduction of the needle and still in the position of fig. 1 trigger 12 is actuated. Because of force of spring 8 acting on support block 9 and releasing of sleeve 10 through trigger 12 sleeve 10 moves outwardly relative to housing 3. During this movement pushing rod 7 will move outwardly. However, in practice this means that pushing rod 7 will remain stationary whilst needle 2 and housing 3 will retract from the animal. In the end position not shown the needle will be completely received in sleeve 10 so that there is no danger from the tip 6 of the needle. During this retracting movement product 14 will remain in position under the skin of the animal and will be placed after removing apparatus 1 from the animal. In fig. 2 the introduction of the injector 1 according to the invention is shown. After introduction of the needle in the skin 17 according to any method known in the art the needle has to be positioned between skin 17 and cartilage 18 being immediately under the skin. Such a structure is e.g. found in ears of most animals. It is important that the needle is displaced over a considerable distance between skin 17 and cartilage 18 to be able to position transponder 14 on a desired location. To prevent the tip 6 of the needle attacking cartilage 18 ball-shaped protrusion 4 is provided which guides the extremity 6 of the needle over the surface of cartilage 18. Through this movement skin 17 of part 15 of the living being is separated from cartilage 18. Although the invention is described above with reference to a simple embodiment of an apparatus provided with the needle according to the invention it has to be understood that further guiding members can be provided to guarantee the path of the needle between the skin and the tissue below. Such guiding members are e.g. described in the European patent application 92203427.7. All such combinations are within the range of the appended claims.

Claims: Hypodermic needle (2) having at least a base portion, a hollow shaft portion and a tip or extremity portion for use with apparatus (1) for injecting an article into the tissue of a living animal, comprising: the base portion for attaching said hypodermic needle to injection apparatus; the hollow shaft portion extending between said base portion and a tip portion, said shaft portion defined by a sidewall, said hollow shaft defining a passage through said needle for the article; the tip or extremity portion of said needle for piercing the skin and tissue of the living animal, a protrusion (4) formed on said needle proximate said extremity portion, said protrusion being formed as part of said hollow shaft portion such that the transition from the protrusion to the shaft of the needle is smooth in all directions including the portion of the protrusion closest to said base portion such that said protrusion will not act as a barb and said needle will be easy to remove, said protrusion being positioned on the needle so as to be near said tip or extremity portion so as to protect tissue such as cartilage or bone of said living animal, characterised in that , said protrusion (4) is formed on said side wall of said needle only in outward direction, and such that the internal diameter of the needle is substantially not decreased in the area of said protrusion. Hypodermic needle according to claim 1, including apparatus attached for injecting a substantially non-deformable article, said apparatus for injecting including a needle pusher means for moving in the passage of said needle to move said substantially non-deformable article through the needle and into the tissue of said animal. Hypodermic needle according to claim 1, wherein the transition between various parts of said protrusion is circular. Hypodermic needle according to claim 1, wherein the tip of the needle is bevelled. Hypodermic needle according to claim 1, wherein said protrusion (4) is provided by depressing a part of the wall of said needle (6).

Inventors: VAN DER AA BARTHOLOMEUS WILHEL, VAN DER AA, BARTHOLOMEUS WILHELMUS JOHANNES
Applicants: TEXAS INSTRUMENTS HOLLAND, TEXAS INSTRUMENTS INC, TEXAS INSTRUMENTS HOLLAND B.V., TEXAS INSTRUMENTS INCORPORATED
Application year: 1992
Main classification: A61M5
IPC codes: A61M5, A61D7