SYRINGE WHICH AUTOMATICALLY MAKES THE HYPODERMIC NEEDLE HARMLESS AFTER USE

Abstract: The aim of this invention is of neutralizing the danger of hypodermic syringes and to make them really monouse, according to the invention the needle (a), which shall be referred to as the perforated stiletto, is provided with a female hook (k), and a cylindrical container (m), inserted coaxially in the piston rod (v) of the syringe, is capable of incorporating the perforated needle (a), by means of a male hooking pawl (n), with its support structure (o) and a cylindrical helicoid pull spring (q).

Description: SYRINGE WHICH AUTOMATICALLY MAKES THE HYPODERMIC NEEDLE HARMLESS AFTER USE. This invention concerns a mechanism incorporated with a piston for syringes, which automatically renders the hypodermic needle harmless after use, said mechanism neutralizes the danger and automatically makes the hypodermic syringes equipped with such non- reusable. The syringes currently on the market improperly defined as monouse have but one single weak protection against accidental injury and may be used, in spite of the written warning "use only once" as many times as desired. The cap even if inserted is not sufficient protection, since any accidental cause whatsoever may cause it to come off leaving the needle exposed and able to injure and even the act of putting it on may itself constitute a potential danger and risk of injury. Some inventions are known which act on the whole syringe and depend upon the user and would be designed in such a way as to protect the needle in a definitive way. There is one type which, after use, retracts the needle inside the canal by means of the piston, with a maneuver carried out by the operator; laborious and in any case not automatic. The needle remains floating inside the canal and cannot injure anyone, as long as no one removes the piston from the cylinder causing it to emerge. There are types involving complicated operations which make the needle disappear and remain enclosed, however always acting or involving and modifying the whole structure of the syringe. These systems involve a total revolutionizing and complete restructuring of machinery from the industrial point of view, and from the point of view of the user, complicated use and dubious safety. The essential aim of this invention is, while leaving unchanged the form and use of the traditional syringe, to give to the industry the facilitated possibility to produce one with only the slightest of added costs and to give to the user the possibility to be able to perform injections as he always has done, with the certainty that his syringe may not accidentally puncture himself or others after use, or that someone else may use it again in any way. This object is achieved with this industrial invention regarding a syringe formed - by a cylindrical body, a piston slidable in said body, a perforated needle, characterized in that said needle is provided with a female hook and in said piston is inserted coaxially a cylindrical container which contains a male hooking pawl with its support structure,operatively connected to a pull helicoidal spring, which is fixed to the same cylindrical container and which is operatively connectable to said female hook to draw back and incorporate said needle in said cylindrical container. In a preferred embodiment, said syringe comprises a cylindrical container open on both sides, which is inserted coaxially in a housing obtained in the normal rod of said piston and which has a rim on its head capable of being housed in a groove of the cap of said piston, said perforated stiletto, or needle, having a female hook, which is slidably supported through a hermetic seal, in a base and which is connected by shearable means to said cylindrical body, a pull helicoid spring extended housed during phase of use inside said cylindrical container and secured at its bottom by a catch and at the other side attached to the support structure of a pawl, which is secured to said cylindrical container by means of at least one pin of shearable material, said pawl with its support structure being inserted, in the phase of use, between the terminal part of said cylindrical container and a canal obtained inside said cap, said canal being closed by a cover of easily perforable material. The condition of the automatic re-entry of the needle, by means of the pawl, is the last pressure activated pushing the piston against the cylindrical body to completely release the liquid through the same needle. Such operation, which permits that the perforated stiletto, or needle, is incorporated in the syringe, is less dangerous and simpler than that which is carried out by the hygienic agents and user communities, as they now insert the protective cap in order to preserve themselves and others. As concerns the sad case of drug addicts who use syringes outdoors, throwing them away wherever they might fall, it is unthinkable that they will throw even a single drop of liquid for which they are so desperate and by injecting themselves up to the last drop, they will certainly activate the mechanism which causes the needle to re- entry. Other advantages of this invention lie in the extreme ease of construction and assembly and the extreme slightness of added costs with respect to the normal syringe; maintaining the identical image and use of the traditional syringe; succeeding in guaranteeing that the needle disappear irrevocably after use that the syringe be utilized only one time. DETAILED DESCRIPTION OF THE INVENTION These advantages and innovative and functional features will be further and understood by every technician of the field by the description which follows and with the aid of the attached illustrations of fig. 1 to 9. as a practical example, but not hardly limited. - In fig. 1 to 5 are shown some components of the syringe according to the invention; - in fig. 6 is shown the syringe ready for use; - in fig. 7 is shown the syringe with the needle drawn back; - Figure 8 represents an enlarged detail with the perforated needle in use and the piston almost at the end of its stroke. - Figure 9 represents the moment of hooking between the pawl and the perforated needle. In the figures the letter (a) represents the perforated stiletto, or needle and (k) the female hook; (c) represents the base of the perforated stiletto, (b) is the neck of the syringe and (d) is the hermetically sealed gasket, as best shown in fig.8; (w) is a membrane of suitable plastic material which fixes the needle (a) to the cylindrical body (u) and is shearable with a predetermined pull force. The letter (e) represents the cap of the piston rod (v) with the easily perforable cover (f) on the cap head at the center; the cap (e) is in especially resilient (springy) material; (g) is the hole or canal to house the hooking pawl (n) ; (h) is the groove to insert the rim (i) of the cylindrical container (m) . The cylindrical container (m) is long enough so as to be inserted in the piston rod (v) and to emerge so as to be able to be inserted stably by means of the rim (i) in the groove (h) of the cap (e) ; the cylindrical container (m) will have in its walls two holes to house the two pins (1) in easily shearable material, inserted in special notches (p) of the support structure (o) to fix it to the same container (m) . The letter (n) represents the male hooking pawl integral with the support structure (o) ; (q) is the helicoid pull spring attached to the support structure (o) of the pawl (n) and to the catch (r) . Some catches (z, x) are placed inside the base (c) and outside the neck (b) of cylindrical body (u) , as shown in fig. 2, and are capable of mantaining the same base (c) stable and of keeping the needle (a) and its hook (k) at the right distance. The pawl (n) will be capable of emerging (being discharged) in the center of the cap, lacerating the thin layer of watertight but perforable material (f) covering the hole (g) suitable for exposing it with the last pressure placed on the piston rod (v) , thanks to the resilience or elasticity of the head (e) of the cap, so as to discharge all the liquid and at the same time hooking itself, permanently in the hollow protuberance (k) of the perforated stiletto or needle (a). When the plastic membrane (w) is broken, perforated metallic stiletto, or needle, (a) can slide in its base (c) and in the watertight seal gasket (d) joined or soldered to the base (c) and inserted inside the neck (b) of the hypodermic syringe. This last abovermentioned pressure will cause the pins to cut the perforable material (1) inserted to jointly hold the cylindrical container (m) with the support casing (o) of the hooking pawl (n) attached to the helicoidal spring (q) in tension, since it is held at the opposite end of the catch (r) to the cylindrical container (m). The spring (q) , once released, while breaking the plastic membrane (w) , will close drawing up inside the cylindrical container ( ) the support casing (o) of the hooking pawl (n) which at the same time will be inserted in the hollow part (k) of the perforated stiletto (a) consequentially pulling also itself inside the cylindrical container (m) and leaving it permanently harmless and non-reusable. In practice, the details of execution may in any case vary in equivalent manner; in form, arrangement or order of the sections or elements, nature of materials used, without however leaving the innovative concept adopted and therefore keeping within the limits of the protection granted for this patent for an industrial invention;

Claims: CLAIMS 1. Syringe which automatically renders the hypodermic needle harmless, formed by a cylindrical body (u) , a piston (v) slidable in said body, a perforated needle, or stiletto (a), characterized in that said needle (a) is provided with a female hook (k) and in said piston (v) is inserted coaxially a cylindrical container (m) , which contains a male hooking pawl (n) with its support structure (o) , operatively connected to a pull helicoidal spring (p) , which is fixed to the same cylindrical container (m) , and which is operatively connectable to said female hook (k) to draw back and incorporate said needle (a) in said cylindrical container (m) . 2. Syringe according to claim 1, characterized in that it comprises said cylindrical container (m) open on both sides, which is inserted coaxially in a housing obtained in the normal rod of said piston (v) , and which has a rim (i) on its head capable of being housed in a groove (h) of the cap (e) of said piston (v) , said perforated needle, or stiletto (a), having a female hook (k) , which is slidably supported, through a hermetic seal (d) in a base (c) and which is connected by shearable means (w) to said cylindrical body (u) , said pull helicoidal spring (q) extended housed during phase of use inside said cylindrical container (m) and secured to its bottom by a catch (r) and at the other side attached to the support structure (o) of said pawl (n) , which is secured to said cylindrical container (m) by means of at least one pin (1) of shearable material, said pawl (n) whith its support structure (o) being inserted, in the phase of use, between the terminal part of said cylindrical container (m) .and a canal (g) obtained inside said cap (e) , said canal (g) being closed by a cover (f) of easily perforated material. 3- Syringe according to the claim 2, characterized in that said cap (e) in its head is extremely resilient and pushing the piston (v) against the top wall of body (u) , it will hide, allowing the pawl (n) to perforate said easily perforable cover (f) and going on to hook (k) itself, emerging, to the female of the perforated needle (a). 4. Syringe according to the claim 2, characterized in that the base of said perforated needle comprises a hermetically sealed gasket (d) which however allows the sliding of the same needle, when it is drawn back. 5- Syringe according to the claim 2, characterized in that said at least one perforable pin (1) , is inserted along the cylindrical container (m) in a respective notch (p) of said support structure (o) of the pawl (n) , such pin (1) , shorn by the last pressure acting on the piston rod, makes sure that the perforated needle (a) is drawn back and incorporated into the cylindrical container (m) together with the pawl (n) , its support structure (o) and the spring (q) contracted.

Inventors: NACCI CARLA, NACCI GAETANO, NACCI, CARLA, NACCI, GAETANO
Applicants: NACCI CARLA, NACCI GAETANO, NACCI, CARLA, NACCI, GAETANO
Application year: 1989
Main classification: A61M5
IPC codes: A61M5