RU2139103C1 - One-time syringe - Google Patents

Abstract

FIELD: medicine. SUBSTANCE: one-time syringe may be used for injections with automatic interlocking of repeated use. Constructional members responsible for interlocking are combined into single block separated from syringe and shaped as nozzle located on tapered projection of syringe. Nozzle body is made as pin 1 of nipple valve with tapered hole 2 at end face and side hole 3 of valve in which needle of perforator 4 is secured. Tapered hole 2 is used for installation of pin 1 on tapered projection 5 of cylinder 6, thus forming nondetachable connection with it by means of glue or pin 7. Cavity of side hole 3 of valve communicates with that of cylinder 6. Other end of pin 1 is fitted with tapered projection 8 for needle, hollow of which communicates with hollow of second side hole 9 provided on pin 1. Both side holes 3 and 9 are closed by nipple 10 made as rubber tube set on pin 1 with interference fit. Rubber tube has sealing belts 11 and 12 at its ends for tight connection with pin 1. EFFECT: improved design. 2 cl, 5 dwg

Description

 The invention relates to medicine and is a disposable injection syringe with automatic reuse lock.

 It is well known that a disposable syringe containing a cylinder with a conical protrusion, a piston with a rod and a needle. It is produced in many countries of the world, its manufacturing technology has been debugged for a long time and is difficult and has been unchanged for many years. Its benefits to mankind are enormous; it cannot be overestimated. The disadvantage of the syringe is the possibility of reusing it by mistake or intentionally, so there has always been a need for a syringe with automatic reuse lock. But despite the fact that in the world there are now about 1000 patents for disposable syringes, there is no worthy replacement for a well-known syringe.

To explain this situation, identify possible shortcomings that impede the introduction of known designs and determine the main criteria that should be the basis for the development of an alternative syringe, an analysis of design flaws in the following countries was carried out:
USSR with pat. 1644968 from 04/27/89 to 18378996 from 05/22/91;
Russia with US Pat. 1761154 from 12.14.89 to 2080881 from 10.06.97;
England with US Pat. 2234175 from 03/21/89 to 2301035 from 05/26/95;
U.S. Pat. 3,291,128 from 12.13.66 by 5,242,405 from 09.93;
France with US Pat. 2652006 from 09/15/89 to 2750052 from 06/21/96;
Germany with US Pat. 3808688 from 08/31/89 to 19528091 from 02/06/97;
GDR with US Pat. 300408 from 08/03/89 to 297917 from 06/01/90.

 The disadvantage of the first group of syringe designs, which make up about 70% of the number of tested, is that during their development the scale factor was not taken into account. This means that the proposed design is feasible only on a large-volume syringe and cannot be mechanically transferred to a small-volume syringe and especially to an insulin syringe - it simply does not fit into them, and if it does, then provide strength to similar but already reduced parts, impossible. This leads to the fact that, taking such a design for implementation, it would be necessary to carry out fundamentally different designs on syringes of different volumes, which complicates and increases the cost of production. An example is the device according to patents: France 2718358 from 07/11/94; Russia 2062118 dated 06.20.96, 2025138 dated 01.22.91, 2019195 dated 01.01.91, etc.

 The disadvantage of the second group of syringes, comprising 50%, is the simplicity with which they can be turned into reusable or syringes that are fundamentally not disposable, since they do not have the means to automatically block reuse. The latter include patent 3808688 from 03.31.89 Germany and patent 2287886 from 03.31.94 England. The essence of the designs is the same for them. In the first case, a folded accordion cover is attached to the base of the needle, and in the second case, an elastic cuff. At the other end, these parts are equipped with protective caps with holes for the needle. After the injection, the cover and, accordingly, the cuff are stretched by hand and the needle is sunk under the cap. Obviously, the addict himself will have to do this. The same group includes syringes in which the pistons at the end of the stroke form an integral connection with the cylinder. Such syringes can be used as reusable without completing the piston. This also includes structures in which the piston is separated at the end of the stroke from the rod. The piston can be easily returned to its original position using a pusher through the opening of the conical protrusion. Examples: Russia, US Pat. 2008933 dated 12.22.89; US Pat. 2217505 from 02.25.91; US Pat. 2035920 dated 13.02.90, etc.

 The disadvantage of the third group of designs, comprising approximately 20%, is their complexity. Of course, in our time, any design, even the most exotic, can be made and its work is debugged, but this does not mean at all that the goal can justify any complexity, 2% of 20% are very complex. Accordingly, there will be a syringe price. Examples: USSR Pat. 1801507 from 04/03/91; France pat. 2704433 from 04.29.93, etc.

 The disadvantage of the fourth group of designs, which makes up almost 100%, is that they to one degree or another predetermine changes for many years of the well-known syringe being produced. Many billions syringes were produced in the world, and every year up to a billion, and no invention can stop this flow, change the established technology for many dozens of plants for years. There is only one way out. An alternative syringe should include a well-known syringe in its construction without any changes.

Any of the four shortcomings in these groups casts doubt on the possibility of introducing the invention, meanwhile, acquaintance with more than 100 patents has shown that even designs with a high degree of protection and automatic reuse blocking have two, three, or even all four of these disadvantages. apart from the disadvantages inherent in specific designs. This circumstance and the fact of the absence of an alternative syringe in medical practice gives the right to conclude: the development of its design goes along a dead end. An analysis of deficiencies in four groups of designs determines the principles that should be taken as the basis for the creation of an alternative syringe that has the greatest chance of introduction:
1. Preservation of technology and production of a disposable syringe.

 2. Unification of structural elements providing automatic blocking on syringes of any volume.

 3. Ensuring high protection of the syringe from attempts to use it as reusable.

 4. Simplicity of design.

 Accordingly, all this is the purpose of the invention. The proposed syringe does not have the closest analogue among devices with automatic reuse lock. It is offered as an option.

 The aim of the invention is to preserve the technology and production of a well-known disposable syringe, as well as the unification of structural elements that automatically block its reuse for syringes of any volume.

 This is achieved by the fact that the structural elements are arranged in a single unit, separate from the well-known disposable syringe, in the form of a nozzle on its conical protrusion, while the nozzle body is a pin of a nipple valve, one end of which is provided with a cavity in the form of a conical hole. Using this hole nozzles mounted on a conical protrusion of the cylinder and forms an integral connection with it. At the same end of the pin there is a side opening of the valve in which the punch needle is installed. The cavity of this hole communicates with the cavity of the syringe barrel. At the other end, the pin is provided with a conical protrusion under the needle and a second side hole, the cavity of which communicates with the cavity of the needle. Both side holes are closed with a nipple in the form of an elastic rubber tube, which is worn on the pin with an interference fit. The ends of the tube are fixed to the pin and form hermetic belts with it. The thickness of the nipple shell, at least above the valve opening, ensures its destruction upon contact with the punch needle from excessive pressure on the nipple when trying to re-suction the liquid and the dry cylinder. The nipple is externally closed by a casing that is mounted on the pin and forms an integral connection with it. The casing is provided with a groove covering both side openings, and the cavity of which communicates with the atmosphere. In the factory-supplied condition of the syringe, a removable liquid intake with a suction tube and a separator in the form of a flexible elastic thread is installed on the conical protrusion of the pin, which is placed with the possibility of its extraction in the cavities of the conical protrusion of the pin and the side hole, between the nipple and the pin in the gap between the side holes, and the end of which is fixed in the valve bore, and the separator thread has a bending stiffness, which prevents the nipple from contacting the punch needle with an excess liquid suction pressure. In order to increase protection against intentional modification of the syringe and turning it into a reusable casing, it has point-in-one fixed connections with a nipple by means of glue in the holes of the casing, and the length of the skirt of the liquid intake from the edge to the end of the conical protrusion is greater than the working length of the separator.

 To explain the disposable syringe device and its operation, a drawing of FIG. 1-5. In FIG. 1 shows a General view of the syringe in the context, in a state of factory delivery. 4: 1 scale, 2 milliliter syringe. In FIG. 2 - section aa; in FIG. 3 - section BB; in FIG. 4 is a view along arrow B; in FIG. 5 is a sectional perspective view of a syringe when attempting to re-fill a fluid.

 The proposed disposable syringe consists of a cylinder 1 with a conical protrusion 2, a piston 3 with a rod 4, a pin 5 with a cavity in the end in the form of a conical hole 6, forming an integral connection with the conical protrusion 2 (either using glue, or a pin, or cold diffusion welding using a dichloroethane plastic solvent), a side opening of the valve 7 with a perforator needle 8 communicating with the cavity of the cylinder 1, a conical protrusion 9 of the pin 5, a side hole 10 communicating with the cavities of the conical protrusion 9 and the needle, nipple 11 worn on tyr 5 with an interference fit and made in the form of a rubber tube with sealing belts 12 and 13 at its ends (sealing is provided either by gluing the ends of the tube with a pin, or rings of 8-10 turns of thread, or by making tight edging on the edges of the tube, or by sealing the edges of the tube mounted on top of the casing), casing 14, fitting the nipple 11 and having an integral connection with the pin 5 (either with glue or a pin 15, or dissolving the plastic with dichloroethane, or pressing) and equipped with a groove 16 that covers both side openings 7 and 10 and passing into the grooves 17 and 18, connecting the gutter with the atmosphere. In addition, the casing 14 has one-piece connections with the nipple 11 by means of glue in the openings 19 and 20, a liquid intake 21 mounted on a conical protrusion 9 in the factory, equipped with a suction tube 22 and a separator 23, in the form of a flexible elastic thread that violates the sealing of the side the hole of the valve 7 and at the same time keeps the nipple 11 from being drawn into the valve hole from excessive pressure on the nipple when the liquid is sucked. The liquid intake 21 is equipped with a metal skirt 24 for injection needles 25. To monitor the exit of gas bubbles, the nipple is made of a fairly transparent type of rubber (such rubber is used on pipettes, surgical gloves), the pin and the casing must be sufficiently transparent.

 The work of a disposable syringe is as follows. The piston 3 is inserted into the cylinder 1 until it stops, and liquid is sucked through the tube 22. The separator 23, separating the nipple 11 from the pin, forms a channel through which fluid flows from the suction pipe 22 into the valve opening 7. At the same time, the separator 23 prevents the nipple 11 from being drawn into the cavity of the valve 7 under the influence of external overpressure, working on bending, and therefore has sufficient bending stiffness, which prevents contact of the nipple 11 with the needle of the perforator 8. Next, remove the fluid intake 21, removing the separator 23 and install the needle 25 in this case. At the same time, the nipple 11 is tightly pressed due to the elastic forces fits to pin 5, sealing both side holes 7 and 10. Then, in an upright position, gas bubbles are forced out and then injected, while the nipple 11 rises, leaving the groove 16 and passes liquid from the valve opening 7 into the side hole 10 and then into the needle . The position of the nipple 11 during injection is shown by a conditional line in FIG. 3 and 5. After injection, the nipple 11 closes the opening of the valve 7 and then works as a check valve, which will not allow to re-fill the liquid. When trying to fill the fluid into the cylinder and remove the piston, a maximum vacuum is created in the cavity of the valve 7 because, after the first injection, the fluid is locked between the piston and the nipple and, therefore, there is no initial air bag. As a result, the nipple is pulled into the valve hole and bursts, pricking on the punch needle. If now we try to displace gas bubbles, then the liquid through the gap in the nipple will fall into the groove, and then flow out through the grooves 17 and 18 without getting into the needle. If there is an attempt from the very beginning to remove the fluid intake and immediately install the needle, and then pour the fluid into the cylinder, then the excess pressure on the nipple will be less than in the first case, which is why it is decisive in choosing the thickness of the nipple shell. This is the case of a dry cylinder when an initial air bag exists between the piston and nipple.

 To protect the separator from deliberate cutting at a place above the end of the conical protrusion 9, it is equipped with a steel skirt to turn the syringe into a reusable fluid intake, and so that the separator cannot be cut in the gap between the end of the conical protrusion and the raised liquid intake, there is a distance from the cut of the skirt to the end of the conical protrusion is greater than the working length of the separator, i.e. its part, which goes under the nipple and further into the valve opening.

 To prevent manipulation of the nipple, which can be pulled over the side openings and thus turn the syringe into a reusable one, it is covered with a casing that is not easy to break. And since the casing has point-in-one fixed connections with the nipple, when removing the casing, the nipple will be torn, and the syringe will fail.

 Experiments have shown that all nodes of the syringe are stable, regardless of the volume of the syringe and the speed of the piston. The design is simple and amenable to automatic assembly. The proposed syringe fully preserves the technology and production of the world famous syringe. With sufficient production and accumulation of nozzles, you can immediately, in the volume of one country, switch to alternative syringes.

Claims (2)

 1. A disposable syringe containing a cylinder with a conical protrusion, a piston with a rod, a needle and structural elements that provide automatic reuse lock, characterized in that, in order to preserve the technology and production of a well-known disposable syringe and unification of structural elements on syringes of any volume, structural elements are arranged in a single unit, separate from the syringe, which is a nozzle on a conical protrusion of the cylinder, the body of which is made in the form of a pin nipple a valve provided at one end with a cavity in the form of a conical hole, by means of which the pin is mounted on the conical protrusion of the cylinder to form an integral connection, and a side opening of the valve in which the needle of the hammer drill is mounted, and the cavity of which communicates with the cylinder cavity, and at the other end provided a conical protrusion under the needle and a second side hole, the cavity of which communicates with the cavity of the needle, and both side holes are closed with a nipple in the form of an elastic rubber tube, worn on a pin with tightness, and the ends of which are fixed on the pin with the formation of airtight belts, in addition, the thickness of the shell of the rubber tube of the nipple at least above the valve hole provides destructive interaction with the needle of the puncher at excessive pressure from an attempt to re-set the fluid and the dry cylinder, and the nipple itself is outside closed by a casing, which is mounted on the pin, forming an integral connection with it, and is equipped with a groove covering both side holes, and the cavity of which communicates with the atmosphere, while in a state of When the syringe is delivered from the factory, a removable liquid intake with a suction tube and a separator in the form of an elastic hollow thread is installed on the conical protrusion of the pin, with the possibility of extracting it in the cavities of the conical protrusion of the pin and the side hole, between the nipple and the pin, in the gap between the side holes, and the end of which fixed in the hole of the valve, and the separator thread has a bending stiffness, preventing contact between the needle of the punch and the nipple at an excessive pressure of suction of the liquid.  2. The disposable syringe according to claim 1, characterized in that, in order to protect it from becoming reusable, the distance from the edge of the skirt of the fluid intake to the end of the conical protrusion of the pin is greater than the working length of the nipple, and the skirt itself is made of metal, while the casing has one-piece point connections with the nipple by means of glue in the holes of the casing.

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