DE2328718C3 - Blood collection device - Google Patents

Description

40

The invention relates to a blood collection device with a cylinder, in which one end with a perforated receiving nozzle for a cannula is provided, with an airtight in the cylinder by means of a Piston displaceable piston and having a central bore for guiding the stamp Cap, whose circular cylindrical collar attached to a circular disk-shaped base part has an internal thread has, by means of which the cap on the opposite in the receiving socket, with an external thread provided end of the cylinder can be screwed on.

Such a blood sampling device is known and in particular is a cylinder with a piston and a stamp as well as one leading to the punch and provided with a central hole on the receiving nozzle for the cannula opposite end of the cylinder screw-on cap by DE-OS 20 03 079 known.

However, this known blood sampling device has the disadvantage in practical work that the withdrawn blood cannot be stored and transported in the blood sampling device itself or in its cylinder. In particular, the cylinder of this blood sampling device cannot be used for h5 centrifuging the blood sample in order to obtain the serum. Rather, the blood must first be transferred to a suitable centrifuge tube for this purpose. This results in increased material and wage costs, which are particularly noticeable in the mass operation of a hospital laboratory.

The invention is based on the object of providing the aforementioned blood sampling device develop in the retracted state of the piston with blood sample contained in the cylinder can be stored and transported without any particular difficulty

According to the invention, this object is achieved in that the base part of the cap has a collar with Internal thread concentric and pointing in the same direction collar protrudes from an external thread has, on which one axially protruding from the piston, concentrically surrounding the punch and with Internally threaded collar can be screwed on.

If now, after drawing up the blood sample, the plunger is completely withdrawn by means of the plunger, the internally threaded collar of the piston reaches the externally threaded one The collar of the cap is in contact and can be adjusted by turning the punch in the appropriate direction fully screwed onto this. This means that even if there is a slight leak in the Piston in the cylinder no blood can get out through the central bore of the cap, because the two Collars screwed onto one another create an additional seal. If now the socket at the other end of the cylinder, after removing the cannula, with a closure cap known per se is provided, the cylinder containing the blood sample is securely closed on both sides and can be be stored or transported.

The stamp can be screwed detachably to the piston in a manner known per se; he lets himself then unscrew after pulling back the piston and screwing the two collars together, so that the part of the stamp protruding from the cap no longer interferes. This version has but the disadvantage that the punch may unscrew itself from the piston prematurely, before the two collars are screwed together.

It is therefore preferably provided in a further development of the invention that the stamp has a predetermined breaking point which is located just outside of the base part of the cap when the piston is withdrawn.

Now, after pulling back the piston and screwing the two collars together, the can be removed from the cap protruding part of the stamp can be broken off by pivoting it sideways.

In order to prevent the aforementioned closure cap from becoming detached from the receiving socket and the Blood sample can thereby at least partially leak out of the cylinder is provided with a cap Internal thread provided, which can be screwed onto a corresponding receiving thread on the receiving socket is.

This cap can preferably be hemispherical on the outside. The cylinder screwed on the underside with such a cap then has the outer shape of a conventional centrifuge tube and can be inserted without difficulty in a centrifuge or in corresponding test tube racks.

In order to achieve an even more secure seal between the receiving socket and the cap, the

does not allow blood to escape even during centrifugation is in Further development of the invention provided, one concentric to the bottom of the opening of the closure cap protruding, when screwing the cap onto the socket into the bore of the same to provide engaging mandrel that closes this hole tightly.

The invention is explained in more detail below in an exemplary embodiment with reference to the drawing. It shows

1 shows a longitudinal section through a blood sampling device according to the invention, in the exploded state of the parts;

Fig. 2 to 4 reduced sectional views of the blood sampling device, namely

Fig. 2 in the position in which the blood sampling device is prepared for blood collection,

F i g. 3 in the locked transport position and

F i g. 4 just opened as a centrifuge tube.

The blood sampling device shown in the drawing, in particular in FIG. 1, consists of a cylinder ί with a booth and attached Receiving nozzle 18 and continuous Mitvelbohrung 20 at one end, one in this cylinder airtightly displaceable and movable by a plunger 4 piston 3 and one of the cylinder on his the end facing away from the receiving socket, screwed onto this cap 2 with a the punch receiving and leading central hole. The lower end 15 of the punch is integrally connected to the piston 3 and carries on the top a hand button 17, which is intended to facilitate the aspiration of the blood sample. The stamp is with a annular notch 16 provided, which acts as a predetermined breaking point and a breaking off of the outer part of the Permitted plunger 4 after the piston has been withdrawn. The predetermined breaking point is therefore in at such a distance from the piston that when the piston is fully retracted, as shown in Fig. 3, lies just outside the closure cap 2.

The closure cap 2 consists of a base part 6 and two protruding from this in the same direction and concentric collars 7 and 8. The outer collar is provided with internal threads 10 and can thus be screwed onto a corresponding external thread 11 at the open end of the cylinder 1.

The other, inner collar 8 has an external thread 9 on which the internal thread 13 of a corresponding Collar 12 can be screwed on, which protrudes from the piston 3 in the same direction as the end 15 of the Stamp 4. The collar 12 surrounds this stamp part 15 concentrically.

The receiving socket 18 at the other end of the cylinder 1 is with a stepped, thin-walled Extension 21 provided through which the bore 20, which is already the bottom of the cylinder and the Receiving connector 18 pulls through, also extends backwards. On this detached part 21, which may be is conical on the outside, what is not shown in the drawing, for the purpose of

κι blood sampling of the corresponding counter cone one Cannula attached.

After the cannula has been removed, the receiving socket 18 can be closed by the closure cap 5 will. This cap has in its cavity

π 22 is an internal thread 23 and with this internal thread is on the external thread 19 of the receiving connector 18 screwable.

The cavity 22 continues in a narrowed part 24, which serves to receive the part 21 on the receiving socket 18 when the closure cap 5 is screwed on. From the bottom of this tapered ^A1. A mandrel 25 protrudes coaxially upwards in the frame 24 and pushes the front end of the bore 20 of the part 21 into the front end of the bore 20 of the part 21 and causes a secure seal there.

The piston 3 is either on the underside, as in FIG. 1 shown, concave, which has certain advantages Bringing the beginning of the blood withdrawal, or else, as shown in FIGS. 2 and 3 shown

j (i In the position shown in FIG. 2, the blood sampling device iss prepared for removal after a cannula has been placed on the socket. Of the The piston is then withdrawn by means of the ram 4 and by rotating the ram with its collar screwed onto the counter-collar in the closure cap 2. Then the stamp 4 is above the Breaking point broken off.

Then the cap 5 is screwed onto the receiving socket 18 and the hi this position

4n in FIG. 3 device shown is now for storage and suitable for transporting the blood sample.

If you want to centrifuge the blood sample, screw it down you simply remove the cap 2 from the upper end of the cylinder 1, the piston 3 being carried along.

In this position shown in Figure 4, the Use the device like a standard centrifuge tube. If necessary, after centrifugation the cap 2 can be screwed on again. In general, this will not happen because the centrifuged blood sample is processed quickly.

For this purpose 2 sheets of drawings

Claims (4)

Patent claims: 1. Blood collection device with a cylinder, one end of which is pierced with a Aufnanmestutzen for a cannula is provided with an airtight in the cylinder by means of a stamp displaceable piston and having a central bore for guiding the punch Cap, whose circular cylindrical collar attached to a circular disk-shaped base part has an internal thread has, by means of which the cap on the opposite to the receiving socket, with The end of the cylinder provided with an external thread can be screwed on, characterized in that that from the base part (6) of the cap (2) to a collar (7) with an internal thread (10) concentric and protruding in the same direction collar (8) which has an external thread (9) on the one axially protruding from the piston (3), concentrically surrounding the punch (4) and with an internal thread (13) provided collar (12) can be screwed on. 2. Biuteninahmevorrichiung according to claim i, characterized in that the punch (4) has a predetermined breaking point (16) which, when retracted The piston (3) is located just outside the base part 2i (6) of the cap (2) 3. Blutentnahmevorrichtunjr according to claim 1 and 2, characterized by a closure cap (5) with an internal thread (23) which attaches to the receiving socket (18) can be screwed on. 4. blood collection device according to claim 3, characterized by a concentric from The bottom of the opening of the cap (5) protruding, when screwing the cap (5) onto the receiving socket (18) into the bore (20) j5 the same intervening and tightly closing Mandrel (25).