EP1028767A1

EP1028767A1 - Method and apparatus for individual destruction of syringe needles by melting under the effect of electric current

Info

Publication number: EP1028767A1
Application number: EP98954513A
Authority: EP
Inventors: Jean Cebollero; Fabrice Bounaix; Bruno Golliard; Jacques Marcandelli
Original assignee: HYPODEST PATENT DEV Co AR; Hypodest Patent Development Co - Arte e Patentes Lda
Current assignee: HYPODEST PATENT DEVELOPMENT Co - PATENTES Lda
Priority date: 1997-11-06
Filing date: 1998-11-04
Publication date: 2000-08-23
Also published as: WO1999024096A1; JP2001522661A; BR9813962A; CA2309303A1; FR2770406A1; AU1159499A; FR2770406B1; US6376792B1; WO1999024096A8

Abstract

The invention concerns a method and an apparatus for individual destruction of syringe needles by melting under the effect of a high intensity electric current. Said apparatus comprises a lower electrode (15) adapted to receive the free end of a needle (12) and to form with it an electric contact, electrically connected to a first terminal (35) of an electric power source (2), a first upper electrode (18) electrically connected to a second terminal (34) of an electric power source (2), and a second upper electrode (27) adapted to be placed in electric contact with the needle (12) surface substantially radially opposite the first upper electrode (18), said second upper electrode (27) being electrically connected to the first terminal (35). The needle (12) is destroyed by being melted flush with the hub (41) between the two electrodes (18, 27).

Description

METHOD AND APPARATUS FOR DESTRUCTION

INDIVIDUAL SYRINGE NEEDLES BY FUSION

UNDER THE EFFECT OF AN ELECTRIC CURRENT

The invention relates to a method and an apparatus for the individual destruction of syringe needles by fusion under the effect of a high electric current.

Used syringe needles are hazardous waste. They constitute in particular a vector of virus transmission. Devices have already been proposed for destroying used syringe needles by fusion under the effect of an electric arc. For example, OA-9300121 describes a needle incinerator device comprising a pair of fixed electrodes for the progressive melting of the needle, and grinding means making it possible to close off the needle residue at the end of melting. This device comprises a piston having an opening through which the needle is introduced. This opening cannot be crossed by the end piece carrying the needle, of larger diameter, which abuts against the piston at the end of the stroke. The piston is moved towards the electrodes until actuating a microswitch which activates an electric motor causing the pinching and the plastic deformation of the needle residue between a pair of clamping jaws moved by the motor. The pair of drilling jaws can also be connected to a source of electrical energy, so as to allow the application of an electric current therebetween, after the needle has been pinched, to seal the interior of the residual end of the needle. This complex and motorized device requires a high-capacity source of electricity and is heavy and bulky. It is not portable and has a life limited to that of the electrodes. In addition, it should be noted that the clamping jaws being interposed between the piston and the electrodes, a residual length of needle is always necessarily left at the end of the needle or syringe tip. However, the inventors have determined that this residual portion of the needle is as dangerous, if not more, than a complete needle. Indeed, it turns out in practice that small dimensions of this residual portion of the needle, far from reducing the risk of injury as might be expected, are in practice the cause of many accidents due to the fact that it is almost invisible and has a false harmless appearance.

Other similar devices have been proposed. In all cases, however, a residual portion of the needle remains projecting at the end of the syringe tip. This end portion can of course be mechanically sectioned using a specific tool. However, the problem then arises again from the danger represented by the detached residual portion which is not destroyed and is, on the contrary, sharp and potentially contaminated. Furthermore, most of the devices for destroying needles using an electric current previously proposed are either bulky and non-portable (in particular powered by the electrical sector), or portable but have insufficient autonomy or are not sufficient effective in melting all needles. In addition, all these devices are extremely expensive, and have a limited lifespan due to rapid wear of the electrodes so that it is not reasonably conceivable to use them to equip the personnel of the health professions (nurses , doctors, dentists, hospital staff, pharmacists, paramedics, rescuers, firefighters, veterinarians ...) or patients (diabetics ...) on a large scale. Throughout the text, the expression “syringe tip” designates, in a syringe comprising a syringe body carrying a needle, the tip which carries the tapered hollow metal rod, called the needle rod, forming the needle proper . The notion of "syringe tip" also similarly encompasses the case where the needle is connected to a flexible tube acting as a syringe body (dialysis or sampling line, etc.). More generally, throughout the text, the term "syringe" applies to any device for injecting or withdrawing liquids into the body and with which a needle is associated and protrudes from a tip, called a syringe tip. Most often, the syringe tip is formed from the female tip of the needle carrying the needle rod, and which is connected to a male tip conjugated to the syringe body. The syringe tip has, at its end by which the needle rod opens, a shoulder extending at least substantially radially outward relative to the needle rod, and this tip is slightly flared towards the syringe body, the assembly between the male and female ends generally being of conical type. This shoulder is larger in diameter than the needle rod.

The invention therefore aims to overcome the aforementioned drawbacks by proposing a method and an apparatus for destruction by which each needle can be completely destroyed without hazardous waste or sharp portion projecting from the syringe tip. More particularly, the invention aims to propose a portable device allowing the needles to be completely destroyed over their entire axial length exceeding the syringe tips.

The invention aims more particularly to propose an apparatus which can be used with all needles, whatever their dimensions, in particular up to a diameter of the order of 1.2 mm.

The invention also aims to propose a device having a large autonomy allowing the destruction of a large number of needles, in particular of more than 80 needles with a diameter of 0.6 mm between two refills or two renewals of the source of 'electric energy. The invention also aims to provide such a device which is particularly simple, reliable, long-lasting, safe to use, and the cost of which is much lower - notably three to five times lower - than that of known prior devices.

The invention further aims to provide a portable device which is particularly ergonomic, easy and inexpensive to use and maintain, and of low weight and dimensions.

Throughout the text, the term "axial" and its derivatives designate a direction parallel to the axis of a needle to be destroyed, and the term "radial" and its derivatives designate a direction perpendicular to the axial direction. In addition, the apparatus is assumed to be generally horizontal and the needle generally vertical with its free end down, although in practice this position is, of course, not compulsory. In addition, the expressions “needle end portion” and “residual needle end portion” designate end portions of the tapered hollow metal rod forming the needle proper, and therefore do not include not the syringe tip.

The invention therefore relates to a method for the individual destruction of syringe needles by fusion under the effect of a high intensity electric current using electrodes connected by a power circuit to a source of electric energy, in which, in a first destruction step, the free end of a needle is applied in electrical contact with a lower electrode electrically connected to a first terminal of the electric power source, the exterior surface of the needle is applied in electrical contact with a first upper electrode electrically connected to a second terminal of the electric power source which is distinct from the first terminal to which the lower electrode is connected, the distance between the electrical contact of the outer surface of the needle with the first upper electrode and the free end of the needle in electrical contact with the lower electrode ieure being adapted so that the electric current established between the lower electrode and the first upper electrode via a needle end portion extending between these electrodes is capable of causing the fusion of this needle end portion, and the needle is gradually melted by sliding its outer surface axially in contact with the first upper electrode as its end portion melts, characterized in that: - the first upper electrode has a free face upper against which a syringe tip can come into axial abutment,

- In a first destruction step, the needle is gradually melted by sliding its outer surface axially in contact with the first upper electrode until the syringe tip carrying the needle axially abuts against the first electrode superior, - in a second subsequent destruction step, a second upper electrode is applied in electrical contact with the outer surface of the needle at least substantially radially opposite the first upper electrode, this second upper electrode being electrically connected to the same first terminal of the electric power source which is separate from the second terminal to which the first upper electrode is connected, so that an electric current is established between the first upper electrode and the second upper electrode through the section of the needle flush with the syringe tip abuts the first upper electrode, whereby destruction is carried out by electrical fusion, flush with the syringe tip, of the residual end portion of the needle s extending from the syringe tip, this residual end portion being destroyed by fusion between the first upper electrode and the second upper electrode, and the fusion residue being further detached from the syringe tip which no longer has projecting protrusions later.

Advantageously and according to the invention, during the second destruction step, the first upper electrode and the second upper electrode are applied against the external surface of the needle by exerting, by manual action, a radial pressure between them tending to approximate by taking the pincer section of the needle.

Advantageously and according to the invention, the second upper electrode is applied with a radial pressure against the outer surface of the needle while the outer surface of the needle is, in opposite, in abutment radially against the first upper electrode carried by a device frame. Thus, according to the method of the invention, during the second subsequent destruction step, destruction is carried out by electrical fusion of the residual end portion of the needle rod, flush with the syringe tip, between the two upper electrodes. The fusion residue is also detached from the syringe tip which no longer has sharp protrusions projecting thereafter. On the contrary, the heat produced by the fusion of the end portion by the two upper electrodes tend to melt, at least partially, the end of the syringe tip, which has the effect of plugging it and presenting a particularly harmless surface appearance.

The residual end portion being destroyed by electrical fusion, no complex mechanical motorized mechanical sectioning device is to be expected, contact of the upper electrodes with this residual portion of the needle can be obtained by manual action. However, nothing prevents the provision of means making it possible to assist or facilitate this manual action, for example a return spring in the direction of the spacing, or on the contrary, the bringing together of the upper electrodes.

It should also be noted that the gradual melting of the needle at high temperature (practically at a temperature above 1300 ° C.) has the effect of bringing the entire metal needle to high temperature, including in the portion of the needle that extends inside the syringe tip. This results in destruction of microorganisms and viruses, and therefore sterilization of the syringe tip.

The invention also extends to an apparatus for implementing the method according to the invention.

The invention therefore also relates to an apparatus for the individual destruction of syringe needles by fusion under the effect of a high intensity electric current, comprising a source of electrical energy and electrodes connected to the source of electrical energy by a power circuit, these electrodes being adapted to be able to be placed in contact with a needle so as to establish between them, via a needle portion extending between these electrodes, an electric current capable of causing the fusion of this portion d needle, these electrodes comprising:

a lower electrode adapted to receive the free end of a needle and form an electrical contact with it, this lower electrode being electrically connected to a first terminal of the source of electrical energy, a first upper electrode adapted to be able to be placed in electrical contact with the outer surface of the needle at an axial distance from the free end of the needle in contact with the lower electrode adapted so that the electric current established between the the lower electrode and the first upper electrode via a needle end portion extending between these electrodes, is able to cause the fusion of this needle end portion, this first upper electrode being electrically connected to a second terminal of the electrical energy source which is distinct from the first terminal to which the lower electrode is connected, characterized in that:

the first upper electrode has an upper free face against which a syringe tip can come into axial abutment,

the electrodes comprise a second upper electrode adapted to be able to be placed in electrical contact with the external surface of the needle at least substantially opposite radially from the first upper electrode, this second upper electrode being electrically connected to the same first terminal from the source of electrical power which is separate from the second terminal to which the first upper electrode is connected, so that an electric current can be established between the first upper electrode and the second upper electrode, through the section of the needle, whereby a residual end portion of the needle projecting from the syringe tip carrying the needle after performing the progressive fusion of the needle between the first upper electrode and the lower electrode , can be destroyed by electrical fusion between the first upper electrode ieure and the second upper electrode, flush with the syringe tip abutting against the first upper electrode, this portion of residual needle end, the fusion residue being further detached from the syringe tip which does not have more later, protruding asperities.

Advantageously and according to the invention, the upper free face of the first upper electrode against which the syringe tip can come into axial abutment has a straight sharp edge against which the outer surface of the needle can be applied radially to establish tangential contact with this straight sharp edge.

Likewise, advantageously and according to the invention, the second upper electrode has an upper free face against which a syringe tip can come into axial abutment, and a straight sharp edge which is defined by this upper free face, and which can be applied radially against the outer surface of the needle to establish tangential contact with this straight sharp edge.

Advantageously and according to the invention, the first upper electrode and / or the second upper electrode is formed of a plate removably mounted on a conductive electrode support.

Advantageously and according to the invention, the plate has several - in particular four - straight sharp edges and is mounted on the electrode support so as to allow the change of the straight sharp edge intended to come into electrical contact with the outer surface d 'a needle. Advantageously, the plate has a square upper free face.

In addition, advantageously and according to the invention, the first upper electrode and / or the second upper electrode is made of tungsten carbide.

Furthermore, advantageously and according to the invention, the device is characterized in that the first upper electrode is mounted fixed relative to a frame of the device and in that the second upper electrode is mounted so that it can be moved radially in translation between a position distant from the first upper electrode where only this first upper electrode is in contact with the outer surface of a needle, and a position brought closer to the first upper electrode where these two electrodes are in electrical contact with the surface outside of a needle.

Advantageously and according to the invention, the second upper electrode is shown integral in translation with a push button adapted to be able to be actuated manually. In addition, the invention also relates to an apparatus for the individual destruction of syringe needles by fusion under the effect of a high intensity electric current, comprising a source of electrical energy and electrodes connected to the energy source electric by a power circuit, these electrodes comprising a lower electrode adapted to receive the free end of a needle and form with it an electrical contact, this lower electrode being electrically connected to a terminal of the source of electric energy, and a first upper electrode adapted to be able to be placed in electrical contact with the outer surface of the needle, this first upper electrode being electrically connected to a terminal of the electrical energy source which is distinct from the terminal to which the lower electrode is connected, characterized in that:

- the axial distance between the lower electrode and the electrical contact established between the outer surface of a needle and the first upper electrode is between 3 mm and 5 mm, in particular is of the order of 4 mm, - the source d electrical energy comprises a voltage source delivering between two terminals a direct voltage between 1.8 V and 2.5 V,

- The power circuit has a total internal resistance between the lower electrode and the first upper electrode via the source of electrical energy, which is less than 50 mΩ so that the device can in particular be portable.

It has in fact been observed that with these values, it is possible to bring the portion of needle between the lower electrode and the first upper electrode to high temperature (greater than 1300 ° C.) and to melt this portion of needle , and this with the shapes and dimensions of the most common needles on the market. In particular, we note that despite the low direct voltage used (less than 2.5 V), we manage to create an intensity greater than 60 A between the two electrodes. Advantageously and according to the invention, the source of electrical energy comprises at least one pair of batteries or accumulators in series, each battery or accumulator delivering a voltage of the order of 1.2 V.

Advantageously and according to the invention, the source of electrical energy comprises several - in particular three - pairs of batteries or accumulators mounted in parallel, each battery or accumulator having a capacity greater than 1500 mAh, in particular of the order of 1800 mAh .

Preferably and according to the invention, the source of electrical energy is formed of rechargeable Cadmium-Nickel accumulators. Furthermore, it is important that the internal resistance of the power circuit be less than 50 mΩ, and be as low as possible, to avoid all resistive losses and voltage drops before the electrodes are supplied. Advantageously and according to the invention, the apparatus is further characterized in that the power circuit comprises at least one controlled electronic switching circuit making it possible to supply or isolate at least one of the electrodes of the corresponding terminal of the source of electrical energy, and in that this controlled electronic switching circuit is adapted to present an internal resistance, in the closed state where the electrode is supplied, which is less than 15 mΩ, in particular of the order of 10 mΩ. Advantageously and according to the invention, the controlled electrical switching circuit comprises a transistor MO S, and the apparatus comprises a voltage booster circuit making it possible to bias the transistor from the source of electrical energy. The voltage booster circuit enables the MOS transistor to be biased at a voltage greater than the voltage delivered by the source of electrical energy. As a voltage booster circuit, it is possible to use, for example, a voltage multiplier assembly, in particular of the Latour type or of the Schenkel type consisting of diodes and capacitors.

Furthermore, the apparatus according to the invention advantageously comprises a secondary electronic circuit making it possible in particular to control the operation of the device (with a start and stop button, indicator lights, a charger circuit for recharging the accumulators from a transformer connected to the mains, a timer circuit for limiting the duration polarization of the electrodes while waiting for a needle to be destroyed, a control circuit for the electronic switching circuit (control and polarization of the switching of the MOS transistor applied to its gate, etc.)). Advantageously and according to the invention, this secondary electronic circuit comprises a circuit with electric power supply capacitor (s) connected to the source of electric energy, and adapted to supply the electronic components of the device during the melting of a needle. . In this way, while an electric current is established between the electrodes and the needle is in the process of melting, all the intensity delivered by the source of electric energy can be supplied to the electrodes, the secondary electronic circuit being supplied. from the electrical energy previously stored in the power supply capacitor (s) circuit.

In practice, it can be seen that the device according to the invention is extremely simple, efficient, compact (its typical dimensions being 170 mm x 70 mm x 43 mm), light weight (less than 550 g), has autonomy. significant electrical power, in particular making it possible to destroy more than 80 needles with a diameter of 0.6 mm between two refills, can be produced at low cost, has a long service life, is particularly ergonomic and simple to use and maintain, and allows destroy each of the needles completely after use without leaving any residual portion projecting from the tip of the syringe or any sharp, dangerous and contaminated residue. It is thus possible to envisage equipping all the personnel of the health professions and / or the patients with a device according to the invention.

The invention also relates to a method and an apparatus characterized in combination in whole or in part with the characteristics mentioned above or below. Other objects, characteristics and advantages of the invention will appear on reading the following description which refers to the appended figures in which:

FIG. 1 is a schematic exploded perspective view of an apparatus according to a preferred embodiment of the invention,

FIGS. 2 and 3 are schematic exterior perspective views of an apparatus according to a preferred embodiment of the invention, respectively from two different viewing angles,

FIG. 4 is a schematic detail view in exploded perspective of an electrode holder cassette and of a push button of an apparatus according to the invention,

FIGS. 5 a and 5 b are schematic views in vertical section respectively illustrating two steps of a method according to the invention,

- Figure 6 is a block diagram of the electronic circuits of an apparatus according to an embodiment of the invention.

The apparatus 1 according to the invention shown in the figures comprises a housing bottom 1 forming a frame receiving a storage battery 2, an electrode-carrying cassette 3 associated with a push button 4, and an electronic card 5. The housing is closed in the upper part by two upper covers 6, 7 one of which covers the storage battery 2, while the other, 7, covers the electrode holder cassette 3 and the electronic card 5. The latter cover 7 is provided with an opening 8 allowing access to the electrode holder cassette 3 and to the electrodes from above, and a lateral opening 9 allowing the cassette 3 to empty the residue of needles melted from the side. The openings 8 and 9 can be formed from a single opening, or from two separate openings. The openings 8, 9 are capped by a jumper 10 removably mounted on the cover 7. This jumper 10 is provided with a circular lumen 11 allowing the passage of a needle 12 to be destroyed. This light 11 has a shape and transverse dimensions greater than those of the syringe tip, so that the latter can pass through the lumen 11.

The electrode holder cassette 3 comprises a piece of insulating material 13 in the general form of a tunnel, provided with lights and openings for receiving the various electrodes. This tunnel-shaped part 13 serves to collect the residues of molten needles, and has a lateral opening 14 disposed opposite the lateral opening 9 of the housing so as to allow these residues to be emptied.

The apparatus comprises a lower electrode 15 fixedly mounted in the electrode holder cassette 3 and having an inclined face 16 at an angle of the order of 45 ° relative to the horizontal, which extends immediately under the light 11 of jumper 10 when it is in place. This lower electrode 15 extends at least over part of the width of the tool-carrying cassette 3, and has a tab 17 extending the lower electrode 15 outside the part 13 laterally and downwards. The lower end of the face 17 of the lower electrode 15 is electrically connected to the electronic card 5, for example by a solder.

The electrode holder cassette 3 also comprises a first electrode support 19 extending along the width of the part 13 forming a tunnel, at a distance from the lower electrode 15 and parallel to the lower edge of its inclined face 16. This first support electrode 19 is extended outside the part 13 forming a tunnel laterally and downwards by a tab 20 whose lower free end is electrically connected to the electronic card 5 for example by welding. This first support 19 is mounted fixed relative to the part 13 forming a tunnel and therefore on the tool-carrying cassette 3, which itself is fixedly mounted on the bottom of the housing 1 forming a frame. Similarly, the lower electrode 15 is mounted fixed relative to the part 13 and is therefore fixed relative to the electrode holder cassette 3 and to the bottom of the housing 1 forming a frame.

The first electrode support 19 receives a first upper electrode 18 which is formed of a tungsten carbide (sintered metal) plate fixed by a screw 21 on the first support 19. A second electrode support 22 is mounted integral with the push button 4 which is itself mounted and guided in translation relative to the part 13 in the form of a tunnel by virtue of two horizontal tabs 23 of the push button 4 sliding in lateral grooves 24 of the part 13. The second electrode support 22 is mounted on a bracket 25 of the push button 4 by means of a pin, and is adapted to be able to be inserted and slide in translation in a rail 26 formed by the part 13 in the form of a tunnel and on an upper horizontal face 47 of the lower electrode 15. The second electrode support 22 receives a second upper electrode 27 which is formed of a plate of tungsten carbide (sintered metal) fixed on this second electrode support 22 by means of a screw 28.

The lower electrode 15, the first electrode support 19, and the second electrode support 22 are formed from pieces of copper or brass. The push button 4 is formed of a piece of synthetic material. A spring is interposed between the push button 4 and the vertical face opposite the tunnel-shaped part 13 so as to return the push button 4 in a position laterally distant from the electrode holder cassette 3.

Each of the upper electrodes 18, 27 is formed of a plate in the general shape of a truncated pyramid, the small base of which comes into contact with the corresponding electrode support 19, 22. The large base 44, 48 of each of these plates forms a free polygonal upper face 44, 48 - notably square - defining several straight sharp edges 29, respectively 30 - notably four straight sharp edges 29, respectively 30 to 90 ° from each other -. The plates forming the first upper electrode 18 and the second upper electrode 27 are therefore removable relative to their respective electrode support 19, 22. When the sharp edge 29, 30 of the insert coming into contact with the outer surface of the needles to be destroyed is worn or deteriorated, it suffices to unscrew the screw 21, 28 and turn the insert 90 ° to present a new sharp edge in new condition. In addition, when all the edges are worn, it is easy to change the pads for new ones. The light 11 of the jumper 10 is adapted to serve as a reference for the start of the introduction of the needle. However, it should be noted that once the needle engaged in the electrodes 15, 18, the lumen 11 no longer acts as a guide, the needle being guided only by the electrodes 15, 18 and not coming into contact with light 11.

The two upper electrodes 18, 27 are mounted so as to be radially opposite from each other. In other words, the sharp edges 29, 30 of the two upper electrodes 18, 27 and their points of contact with the outer surface of the needle are located in the same plane which is at least substantially radial to the needle.

The apparatus further comprises a connection socket 32 for an external electrical supply (the sector, or a transformer, or a battery charger circuit), as well as a side button 31 for operating.

As can be seen in the diagram in FIG. 6, the first upper electrode 18 is electrically connected, via the first electrode support 19, to the positive terminal 34 of the storage battery 2. The lower electrode 15 and the second upper electrode 27 are connected, via a controlled electronic switching circuit 33, to the negative terminal 35 of the storage battery 2. The function of the switching circuit 33 is to electrically connect the electrodes 15, 27 to the negative terminal 35 of the storage battery 2 when the operator presses the button 31 for starting. The switching circuit 33 also has the function of isolating the electrodes 15, 27 of the negative terminal 35 of the storage battery 2 when the device is out of function. The accumulator battery 2 consists of three pairs of accumulators 2, the two accumulators of the same pair being mounted in series, the different pairs of accumulators 2 being mounted in parallel between the positive 34 and negative 35 terminals of the battery thus constituted. Each accumulator delivers a voltage of the order of 1.2 V, so that a direct voltage of the order of 2.4 V is delivered between the terminals 34, 35 of the battery 2. Each accumulator has a capacity greater than 1500 mAh, in particular of the order of 1800 mAh. The accumulators are preferably and according to the invention, rechargeable cadmium-nickel accumulators. They are also chosen to have a low internal resistance. It should be noted that it is necessary to take care of the internal resistance of the accumulators themselves, the resistance of the connecting wires, and the internal resistance of the switching circuit 33, the entire power circuit having to present a value. less than 50 mΩ. In addition, by placing the pairs of accumulators 2 in parallel, the current delivered by each accumulator is divided accordingly. Thus, this makes it possible to increase the duration during which the current can be delivered. Simultaneously, the mounting of the accumulators makes it possible to reduce the internal resistance of the accumulator battery 2.

The controlled electronic switching circuit 33 advantageously and according to the invention comprises a MOS transistor with a switching field effect polarized by a voltage booster circuit 45 (voltage multiplier of the Latour or Schenkel type) making it possible to polarize it from the storage battery 2.

The output of the voltage booster circuit 45 is connected to the gate of the MOS transistor. The source of the transistor is connected to the negative terminal 35 of the battery 2, while its drain is connected to the electrodes 15, 27 which must be connected to or isolated from this terminal 35.

A secondary electronic circuit 36 makes it possible to control the operation of the device. This circuit 36 is connected to the positive and negative terminals of the storage battery 2 and includes a circuit (s) 39 of electric power supply which allows to accumulate the electric energy necessary for the operation of the various electronic components of the device while the electrodes 15, 18, 27 are supplied during the melting of a needle 12. This circuit 39 comprises for example a capacitor connected between the terminals 34, 35 via a diode. In the embodiment shown in FIG. 6, the secondary electronic circuit 36 comprises a circuit 37 for charging the storage battery 2, this circuit 37 being connected to the mains socket 32. This charger circuit 37 is for example formed by a rectifier and a circuit forming a current source. The secondary electronic circuit 36 also comprises a logic control circuit 38 of the switching circuit 33 capable of delivering a control signal when the operator actuates the button 31 for starting operation. In addition, the circuit 38 includes the capacitor circuit (s) 39 which supplies the electrical power to this circuit 38, and the various circuits managing the operation of the device.

The power circuit formed by the storage battery 2, and between the positive terminal 34 of the storage battery 2 and the first upper electrode 18 on the one hand, and between the negative terminal 35 and the lower electrode 15, via the switching circuit 33, on the other hand, is adapted to present a total internal resistance as low as possible, and which is less than 50 mΩ.

Figures 5a, 5b and 6 show the general arrangement of the electrodes during the destruction of a needle 12. As can be seen, during the first destruction step, the operating button 31 is actuated, then applied the free end 40 of the needle 12 in contact with the lower electrode 15, more precisely in contact with the inclined face 16 of this lower electrode 15. The external surface of the needle 12 is then applied to the contact with the edge live 29 of the first upper electrode 18. The apparatus being in operation, an electric current is established, which causes the end portion 43 of the needle extending between the edge 29 of the first to merge. upper electrode 18 and the inclined face 16 of the lower electrode 15. As the needle is destroyed and fused, the operator gently pushes the syringe down. It should be noted that the inclination of the inclined face 16 of the lower electrode 15 oriented towards the first upper electrode 18 tends to keep the outer surface of the needle 12 in contact with the sharp edge 29 of the first upper electrode 18 The high intensity of the electric current flowing through this end portion 43 of the needle has the consequence of bringing it to a very high temperature (in particular to a temperature above 1300 ° C.) and therefore of melting this portion of needle. In addition, this very high temperature propagates inside the needle 12 as far as the end piece 41 which carries the needle 12, or even inside the body of the syringe itself. In practice, it has been possible to measure that the temperature inside the portion of the needle extending in the end piece 41 happens to be greater than 350 ° C., and allows sterilization of this portion 49 of the needle and the end piece 41. The fusion residues from the end portion 43 of the needle fall along the inclined face 16 inside the electrode holder cassette 3 and are collected inside the shaped part 13 tunnel.

The needle 12 is thus destroyed until the end piece 41 abuts against the upper free face 44 of the first upper electrode 18 and possibly against the upper free face 48 of the second upper electrode 27, according to the distance presented. between the upper electrodes 18, 27. To complete the destruction of the needle, the operator then manually actuates the push button 4 in order to bring the second upper electrode 27 closer to the needle 12, as shown in FIG. 5b. It should be noted that this second upper electrode 27 is connected to the negative terminal 35 of the storage battery 2, the switching circuit 33 being closed. To do this, a conductor 42 is preferably provided directly electrically connected to the second electrode support 22, and this although this second electrode support 22 rests in fact on the flat conductive face 47 of the lower electrode 15. In Indeed, it is thus ensured that the power supply of the second upper electrode 27 is of good quality (low resistance). Likewise, the tabs 17, 20 for the electrical connection of the first electrode support 19 and of the lower electrode 15, respectively, with the electronic card 5 are directly welded and electrically connected to the electronic circuit formed by the electronic card 5. Thus , and thanks simultaneously to the use of a MOS transistor of low internal resistance, it is possible to produce a power circuit of low internal resistance so that the difference of potential between the electrodes corresponds at least substantially to the voltage delivered by the storage battery 2 between these terminals 34, 35.

In the position shown in FIG. 5b, it should be noted that the free end 43 of the residual needle portion 12 is no longer in contact with the lower electrode 15 since, in general, a certain fusion of the portion 43 has intervened beforehand. In the embodiment shown, advantageously and according to the invention, the two upper electrodes 18, 27 are diametrically opposite with respect to the cylindrical outer surface of the needle 12, and their sharp edges 29, 30 in electrical contact with this surface exterior at least substantially parallel. By bringing the second upper electrode 27 in contact with the outer surface of the needle 12, opposite the first upper electrode 18, the electric current is established radially through the thickness of the needle 12, which has the effect of causing its merger. The residual portion of needle 12 is destroyed by fusion flush with the end piece 41 without any projecting part being left. Furthermore, the heat released between the electrodes 18, 27 has the effect of at least partially melting the end portion 43 and the portion 49 of needle embedded in the end piece 41, and the synthetic material constituting the end piece 41, which clogs the opening opening of the residual portion 49 of the needle inside the end piece 41. When the user releases the push button 4, the latter is recalled laterally outwards so that the second upper electrode 27 moves laterally and radially away from the first upper electrode 18.

The secondary electronic circuit 36 advantageously comprises indicator lights making it possible in particular to indicate that the device is operational after actuation of the activation button 31, or that the charging of the storage battery 2 is in progress, or an alarm of temperature overshoot of the electric power circuit (MOS transistor). The secondary electronic circuit 36 also advantageously comprises a timing circuit 46 comprising a timing enabling the switching circuit 33 to be closed by authorizing the destruction of a needle 12 only during one predetermined duration, for example of the order of 15 seconds, after which the switching circuit 33 is automatically returned to the open state.

Furthermore, the logic circuit 38 for controlling the switching circuit 33 comprises temperature control means adapted to interrupt the electrical supply to the electrodes, that is to say to control the switching circuit 33 in the open state ( by applying a blocking signal of the MOS transistor on its gate), when the temperature of the accumulators 2 exceeds a predetermined value. These temperature control means are adapted to authorize again the electrical supply of the electrodes, that is to say the closing of the switching circuit 33 (i.e. the application to the gate of the MOS transistor of a signal placing it in the on state) when the temperature of the accumulators drops below this predetermined value (that is to say to a normal value). These temperature control means advantageously comprise an element sensing the operating temperature of the MOS transistor itself. Indeed, the overheating of the MOS transistor and of the accumulators are related phenomena. It should be noted that this thermal protection is favorable to the lifespan of the storage battery 2 because, on the one hand, it prevents overheating of the storage batteries 2 and, moreover, it requires a rest time after each initiation of overheated. The invention thus makes it possible to carry out the total destruction of the needles in an extremely simple and effective manner. In particular, the destruction of the needle flush with the end piece 41 promotes sterilization, and closes the opening opening of the residual metallic portion 49 of the needle passing through the end piece 41. This destruction is due to the fusion of the needle by Joule effect. The portion 49 of the needle remaining embedded in the tip 41 of the syringe is blunt, is no longer sharp or pointed and does not protrude outside so that it is completely harmless. The pressure exerted by the user on the push button 4 can aid destruction but is not in fact useful as soon as the electrical contact between the upper electrodes 18, 27 is established. In practice, one can obtain sufficient electrical contact for destruction, using the force of a single finger exerting pressure on the push button 4. The upper electrodes 18, 27 provided with bevelled sharp edges 29, 30 also facilitate the destruction by fusion of the needle by creating a zone of concentration of the electric current. The fact that they are made of tungsten carbide is also favorable, in particular for questions of longevity.

The invention can be the subject of numerous variants with respect to the embodiment described above and represented in the figures. In particular, it is possible to provide an additional switching circuit to control the supply of the second upper electrode 27. It should be noted that the dimensional choices retained, and in particular the distance between the lower electrode 15 and the first upper electrode 18, between 3 and 5 mm, in particular of the order of 4 mm; mounting the six accumulators and choosing a delivered voltage between 1.8 and 2.5 V, in particular of the order of 2.4 V; and the realization of the power circuit with a low internal resistance, make it possible to optimize the dissipation of electrical energy by Joule effect within the needle and to finally obtain a good overall efficiency of the fusion from a low number of small batteries.

Claims

CLAIMS 1 / - Process for the individual destruction of syringe needles by fusion under the effect of a high intensity electric current using electrodes connected by a power circuit to a source of electric energy (2) , in which, in a first destruction step, the free end (40) of a needle (12) is applied in electrical contact with a lower electrode (15) electrically connected to a first terminal (35) of the source d electrical energy (2), the outer surface of the needle (12) is applied in electrical contact with a first upper electrode (18) electrically connected to a second terminal (34) of the electrical energy source (2) which is distinct from the first terminal (35) to which the lower electrode (15) is connected, the distance between the electrical contact of the outer surface of the needle (12) with the first upper electrode (18) and the end free (40 ) of the needle (12) in electrical contact with the lower electrode (15) being adapted so that the electric current established between the lower electrode (15) and the first upper electrode (18) via an end portion ( 43) of the needle extending between these electrodes (15, 18) is capable of causing the fusion of this end portion (43) of the needle, and the needle (12) is gradually melted by sliding its axially outer surface in contact with the first upper electrode (18) as its end portion (43) melts, characterized in that:

- using a first upper electrode (18) which has an upper free face (44) against which a syringe tip (41) can come into axial abutment, - in a first destruction step, the needle (12) is gradually melted ) by sliding its outer surface axially in contact with the first upper electrode (18) until a syringe tip (41) carrying the needle (12) axially abuts against the first upper electrode (18) , - in a second subsequent destruction step, we applies a second upper electrode (27) in electrical contact with the outer surface of the needle (12) at least substantially opposite radially from the first upper electrode (18), this second upper electrode (27) being electrically connected to the same first terminal (35) of the electric power source which is separate from the second terminal (34) to which the first upper electrode (18) is connected, so that an electric current is established between the first upper electrode (18) and the second upper electrode (27) through the section of the needle (12) flush with the syringe tip (41) in abutment against the first upper electrode (18), whereby a destruction by electrical fusion at the level of the syringe tip (41), of the residual end portion (43) of the needle (12) projecting from the syringe tip (41), this portion end (43) residue being destroyed by fusion between the first upper electrode (18) and the second upper electrode (27), the fusion residue being further detached from the syringe tip (41) which no longer has protruding projections .

2 / - Method according to claim 1, characterized in that a second upper electrode (27) is used which has an upper free face (48) against which a nozzle (41) of syringe can come into axial abutment.

3 / - Method according to one of claims 1 and 2, characterized in that during the second destruction step, the first upper electrode (18) and the second upper electrode (27) are applied against the outer surface of the needle (12) by exerting, by manual action, a radial pressure between them tending to bring them closer by taking the section of the needle (12) in pincers.

4 / - Method according to one of claims 1 to 3, characterized in that the second upper electrode (27) is applied with a radial pressure against the outer surface of the needle (12) while the outer surface of the 'needle (12) is, in opposite, abutted radially against the first upper electrode (18) carried by a frame (1) of apparatus.

5 / - Apparatus for the individual destruction of syringe needles by fusion under the effect of a high intensity electric current, comprising a source of electrical energy (2) and electrodes connected to the source of electrical energy (2) by a power circuit, these electrodes being adapted to be able to be placed in contact with a needle (12) so as to establish between them, via a needle portion extending between these electrodes, an electric current capable of causing the fusion of this needle portion, these electrodes comprising:

- A lower electrode (15) adapted to receive the free end (40) of a needle (12) and form with it an electrical contact, this lower electrode (15) being electrically connected to a first terminal (35) of the electric power source (2), - a first upper electrode (18) adapted to be able to be placed in electrical contact with the outer surface of the needle (12) at an axial distance from the free end (40) of l needle (12) in contact with the lower electrode (15) adapted so that the electric current established between the lower electrode (15) and the first upper electrode (18) via an end portion (43) of needle extending between these electrodes (15, 18), or capable of causing the fusion of this end portion (43) of the needle, this first upper electrode (18) being electrically connected to a second terminal (34) of the electric power source (2) which is dis tincture of the first terminal (35) to which the lower electrode (15) is connected, characterized in that:

the first upper electrode (18) has an upper free face (44) against which a syringe tip (41) can come into axial abutment,

the electrodes comprise a second upper electrode (27) adapted to be able to be placed in electrical contact with the external surface of the needle (12) at least substantially opposite radially from the first upper electrode (18), this second electrode upper (27) being electrically connected to the same first terminal (35) of the electric power source (2) which is distinct from the second terminal (34) to which the first upper electrode (18) is connected, so that an electric current can be established between the first upper electrode (18) and the second upper electrode (27), through the section of the needle, whereby a residual end portion (43) of the needle projecting from a tip (41) of syringe carrying the needle (12) after having carried out the progressive fusion of the needle (12) between the first upper electrode (18) and the lower electrode (15), can be destroyed by electric fusion between the first upper electrode (18) and the second upper electrode (27), flush with the syringe tip (41) in abutment against the first upper electrode (18), the fusion residue of this residual end portion of needle being further detached from the syringe tip (41) which no longer has protruding projections.

6 / - Apparatus according to claim 5, characterized in that the upper free face (44) of the first upper electrode (18) has a straight sharp edge (29) against which the outer surface of the needle (12) can be applied radially to establish tangential contact with this straight sharp edge (29).

II - Apparatus according to one of claims 5 and 6, characterized in that the second upper electrode (27) has an upper free face (48) against which a syringe tip (41) can come into axial abutment, and an edge straight sharp (30) which is defined by this upper free face (48), and which can be applied radially against the outer surface of the needle (12) to establish tangential contact with this straight sharp edge (30).

8 / - Apparatus according to one of claims 5 to 7, characterized in that the first upper electrode (18) and / or the second upper electrode (27) is formed of a plate mounted removably on a support electrode (19, 22).

9 / - Apparatus according to claim 8, characterized in that the plate has several - notably four - straight sharp edges (29, 30) and is mounted on the electrode support (19, 22) so as to allow the change of the right sharp edge (29, 30) intended to come into electrical contact with the outer surface of a needle (12). 10 / - Apparatus according to one of claims 5 to 9, characterized in that the first upper electrode (18) and / or the second upper electrode (27) are made of tungsten carbide.

11 / - Apparatus according to one of claims 5 to 10, characterized in that the first upper electrode (18) is mounted fixed relative to a frame (1) of the apparatus and in that the second upper electrode (27 ) is mounted so that it can be moved radially in translation between a position remote from the first upper electrode (18) where only this first upper electrode is in contact with the outer surface of a needle (12), and a position close to the first upper electrode (18) where these two electrodes (18, 27) are in electrical contact with the outer surface of a needle (12).

12 / - Apparatus according to claim 11, characterized in that the second upper electrode (27) is mounted integral in translation with a push button (4) which can be actuated manually. 13 / - Apparatus according to one of claims 1 to 12, characterized in that:

- the axial distance between the lower electrode (15) and the electrical contact established between the outer surface of a needle (12) and the first upper electrode (18) is between 3 mm and 5 mm, in particular is order of 4 mm,

the electrical energy source (2) comprises a voltage source delivering between the two terminals (34, 35) a direct voltage between 1.8 V and 2.5 V,

- the power circuit has a total internal resistance between the lower electrode (15) and the first upper electrode (18) via the electrical energy source (2), which is less than 50 mΩ so that the device can including being portable.

14 / - Apparatus according to claim 13, characterized in that the electrical energy source (2) comprises at least one pair of batteries or accumulators, the two batteries or accumulators of the same pair being mounted in series, each battery or accumulator delivering a voltage of the order of 1.2 V.

15 / - Apparatus according to claim 14, characterized in that the electrical energy source (2) comprises several - notably three - pairs of batteries or accumulators mounted in parallel, each battery or accumulator having a capacity greater than 1500 mAh , in particular of the order of 1800 mAh.

16 / - Apparatus according to one of claims 14 and 15, characterized in that the source of electrical energy (2) is formed of rechargeable Cadmium-Nickel accumulators.

17 / - Apparatus according to one of claims 13 to 16, characterized in that the power circuit comprises at least one electronic switching circuit (33) controlled to supply or isolate at least one (15, 27) of the electrodes of the corresponding terminal (35) of the electrical energy source (2), and in that this controlled electronic switching circuit (33) is adapted to present an internal resistance, in the closed state where the 'electrode (15, 27) is supplied, which is less than 15 mΩ, in particular of the order of 10 mΩ.

18 / - Apparatus according to claim 17, characterized in that the controlled electrical switching circuit (33) comprises a MOS transistor, and in that it comprises a voltage booster circuit making it possible to bias the transistor from the source d electrical energy (2).

19 / - Apparatus according to one of claims 5 to 18, characterized in that it comprises a secondary electronic circuit (38) allowing in particular to control the operation of the apparatus, and in that this secondary electronic circuit (38) comprises a circuit (39) to capacitors) of electrical supply connected to the source of electrical energy (2), and adapted to supply the electronic components of the device during the melting of a needle (12).