IL46554A - Injection syringe with sealed needle guard - Google Patents

Abstract

1450514 Injection syringes PHILIPS GLOEILAMPENFABRIEKEN NV 3 Feb 1975 [6 Feb 1974] 4522/75 Heading A5R An injection syringe 1 comprises a needle guard 14 provided with a thickened portion or ridge 15 adjacent to the needle mount 12 whereby it is sealed in place on the needle by a locking ring 16, (26) which is joined by breakable connections 20, (30) either to the body of the syringe 2, Fig. 1 or to a holder for that body (22, Fig. 2). The locking ring is so arranged that the needle guard cannot be removed without breaking the breakable connections so that the user may be assured of the needle's sterility. As described the locking ring is in the form of a hollow cap with a bore through its top which is larger in diameter than the main part of the needle guard but smaller than the thickened portion. The locking ring may for example be made from clear plastics in which case the breakable connections may be narrow strips of plastics. [GB1450514A]

Description

Injection syringe h, sealed needle guard K.V, Philips" ¾loeil2impenfa¾rieken C:-44445 "injection syringe wit sealed needle guard." The invention relates to an injection syringe comprising a cartridge which is provided with a needle mount with injection needle and which may be disposed in a cartridge holder, a needle guard which is disposed over the injection needle, which guard at one end is detachably connected to the needle mount, the needle guard being provided with a thickened portion or ridge at the side of the needle mount.

Such an injection syringe is known from Netherlands Patent Specification 133,6 9.

At the location of the thickened portion or ridge the needle guard is frictionally clamped onto a longitudinal sleeve which forms part of the needle holder and in which the injection needle is secured. Thus, a sterile sealing of the needle is achieved. Obviously, sterility of the needle is an essential requirement when using the injection syringe. The known injection syringe has the drawback that the user cannot satisfactorily ascertain the sterility of the needle. More specifically., the user cannot ascertain whether the needle guard has been removed previously or, for example, has come loose during transit and has subsequently been replaced in the original position. In fact, the user not assured of the sterility of the injection needle .

The Applicant has developed an injection needle of the above-mentioned type which does not have said drawback. More specifically, the injection syringe according to establish visually whether the needle guard has been removed previously.

For this purpose the injection syringe according to the invention comprises a safety member provided with a central bore which via the bore is slipped over the needle guard and which is provided with breakage means which connect the member detachably and irreversibly to the cartridge or the cartridge holder, the smallest diameter of the bore ranging between the diameter of the needle guard and that of the thickened portion or ridge.

When using the injection syringe according to the invention the safety member is to be removed" before the needle guard can be detached. The safety member is removed by turning said member relative to the cartridge or by a exerting a force on it which is directed away from the cartridge. As a result of this, the means which connect the safety member to the cartridge or cartridge holder are broken and the safety member which is thus released may be slipped back over the needle guard and eventually removed. Subsequently, the needle guard may be removed.

The user of the injection syringe according to the invention can ascertain visually whether the breakage means are still intact and from this conclude whether the needle guard has been removed previously and thus whether the sterility is affected.

The safety member may have different embodiments. For example, the safety member may be a cylindrical body provided with a central bore of which the lower end engages with or substantially engages with the ridge of the needle guard. The lower art of the c lindrical body- is provided with breakage means,- for example . taking the form of strips which by their free ends are secured to the cartridge or cartridge holder.

In a favourable embodiment the safety member is a hollow body taking the form of a cap which is open at the lower end, which at said end is provided with the breakage means and at the top contains a central bore whose diameter ranges between that of the needle guard and that of the thickened portion or ridge.

In said favourable embodiment the ridge or protrusion is disposed inside the cap of the safety member and the connection of the needle guard to the needle holder is protected additionally.

According to a further favourable embodiment the bottom of the cap has an outer diameter which corresponds to the outer diameter of the part of the cartridge holder which faces the cap and is provided with breakage means in the form of a shoulder, strips or wires which by their free ends are secured to the part of the cartridge holder which faces the cap.

In said embodiment the dimensions of the cap are adapted to those of the cartridge holder, so that the ca may be regarded as an extension of the holder. This ensures that external forces acting on the injection syringe, for example in transit, less easily give rise to damaging of the breakage means and detachment of the cap.

The invention will be described in more detail with references to the drawing.

In the drawing, Fi . 1 shows a lon itudinal section of an embodi- ment of an injection syringe according to the invention, the safety member being connected to the cartridge; Fig. 2 shows a longitudinal section of a different embodiment of the injection syringe according to the invention, the safety member being connected to the cartridge holder.

In the drawing the reference numeral 1 denotes a cartridge. The cartridge 1 comprises a cylindrical vial 2 which contains an injection fluid 5 between a stopper 3 at the front of the vial 2 and a plunger k at the rear of the \rial . At the front the vial is provided with a neck 6 having a flange 7 · The cartridge 1 furthermore comprises a needle mount 8 which by a flange portion 9 is clamped onto the front face of the vial 2 by means of an aluminium ring 1 0 . The ring 1 0 fits around the flange of the vial and the needle mount, a flange portion 1 1 of the stopper 3 being disposed between the two other flanges. At the end which faces away from the stopper 3 the needle mount is provided with a cylindrical sleeve 1 2 in which an injection needle 1 3 which is bevelled at both ends is secured. A needle guard 1 ^ tightly fits around the injection needle 1 3 and is frictionally secured to the sleeve 1 2 of the needle mount 8 by means of a thickened portion or ridge 1 5 · Around the needle gurad a safety member 1 6 is disposed, which may for example be made of a transparent synthetic material. The safety member 1 6 has the shape of a cap 17 which is open at the bottom, whose side wall is cylindrical and whose top surface 1 8 has a central bore 1 9 . Through said central bore 1 9 the part of the needle guard 1 which is disposed above the ridge 1 5 extends. The diameter of the central bore 1 9 is smaller than the o\iter diameter of the ridge 1 5 but greater than the outer diameter of the part of the needle guard 1 4 which is disposed above the ridge. The lower side of the top portion 1 8 of the cap 1 7 engages or substantially engages with the ridge 1 5 · At the lower end of the cap 1 7 breakage means 20 are provided in the form of for example plastics strips which with their free ends are attached to the ring 1 0 of the cartridge 1 .

In Fig. 2 the reference numerals 1 - 1 5 denote similar components of the injection syringe of Fig. 1 . The cartridge 1 shown in Fig. 2 is disposed in a cartridge holder 2 1. The cartridge holder 21 corresponds to that described in the previously cited Netherlands Patent Specification 1 33 > 6¾9 anc consists of a hollow cylinder 22 with a cross-piece 23 · At its front end the cylinder 22 terminates in a neck 2k whose internal diameter is exactly such as to accommodate the ring 1 0 of cartridge 1 without friction. In order to lock the cartridge 1 inside the cartridge holder 21 the front end of the holder 21 is provided with cams 25 · Around the needle guard a safety member 26 is disposed which for example made of a transparent synthetic material. The safety member 26 has the shape of a cap 27 which is open at ihe bottom end, whose side wall is substantially conical and whose top portion 28 is provided with a central bore 29 · The part of the needle guard I k which is disposed above the ridge 1 5 extends through the central opening 29 · The diameter of the opening 29 is smaller than the outer diameter of the ridge 1 5 but greater than the outer diameter of the part of the needle side of the top portion 28 of the cap 27 engages or sub- stantially engages with, the ridge 1 5 · At the bottom the cap 27 s provided with breakage means 30 in the form of for example strips made of a transparent synthetic material which by their free ends are attached to the top of the cartridge holder 21v The diameter of the cap 27 at the i bottom corresponds to the diameter of the cartridge holder 21.

When using the injection syringe according to the invention, it is first ascertained .whether the breakage means 20 , 30 are still intact so as to check the sterility.

Subsequently, the safety member 1 6 , 26 is rotated manually, the breakage means 20 , 30 then breaking off or being toin off. The safety member which is thus released is slipped back over the needle guard 14 and removed. Hereupon the injection syringe is ready for application. For this, the plunger is pushed forward with the aid of a plunger rod, not shown. The pressure then exerted on the injection liquid 5 causes the central part 31 of the stopper 4 to bulge up and expand. When the pressure suffices the central part 31 will burst either spontaneously or after contact with the bevelled rear end of the needle 13. Thereupon the needle guard 14 is removed, the air pushed out and the needle inserted into the body of a patient.

A further displacement of the plunger results in the injection liquid 5 being injected into the body of the patient via the needle 13.

Claims (3)

PHN.7339 CLAIMS :

1. An injection syringe which comprises a cartridge which is provided with a needle mount with injection needle and which may be disposed in a cartridge holder, a needle guard disposed over the injection needle which guard at one end is detachably connected to the needle mount, the needle guard at the side of the needle mount being provided with a thickened portion or ridge, characterized in that the injection syringe comprises a safety member which is provided with a central bore, which member via the bore is slipped over the needle guard and which is provided with breakage means which detachably and irreversibly connect the member to the cartridge or the cartridge holder, the smallest diameter of the bore ranging between the diameter of the needle guard and that of the thickened portion or ridge.

2. An injection syringe as claimed in Claim 1, characterized in that the safety member is a hollow body in the form of a cap which is open at the lower end, which cap at said end is provided with the breakage means and at the top has a central bore whose diameter ranges between that of the needle guard and that of the thickened portion or ridge.

3. An injection syringe as claimed in Claim 2, characterized in that at the lower end the cap has an outer diameter which corresponds to the outer diameter of the part of the cartridge holder which faces the cap and furthermore at the lower end is provided with breakage means in the form of a shoulder, strips or wires which by their free ends are attached to the part of the cartridge