Medical sample introducing apparatus in an analyzer

The invention relates to a sample input device for the input of medical samples, preferably blood samples, from different sampling vessels into an analyzer, the sample being transported between the sample input and the measuring cells of the analyzer via gas-tight sample lines.

Such input devices are known, for example, from medical laboratory operations, where they are used, for example, for blood analysis or other measurements of body fluids. In many cases, analyzers are only specialized in one type of sample input, so that, for example, their input device only allows the sample to be input with the aid of a capillary or a syringe.

There was therefore even earlier the desire to develop sample input devices which were suitable both for sample input using a plunger syringe and capillary without having to undertake laborious adaptation work.

For example, from EP 0 297 082 an analyzer for examining body fluid samples has become known which has a rotatable docking disc which can be brought into connection in different rotational positions with a filler neck of the sample feed line of the analyzer. The sample can also be fed in via this docking disk, whereby it can either be sucked in by means of a hose pump or injected into the sample feed. The advantage of such a sample input system is that from the input element of the analyzer, all sample, calibration and cleaning media supplied within the analyzer cover the same sample path and thus the same measurement conditions prevail for all media, in contrast to known devices which are used for different sampling vessels have different entry positions.

A sample input device similar to that in EP 0 297 082 is described in DE 38 90 175 C1. In this input device, a distributor disk is provided which is rotatably mounted about an axis and which has several input elements which are arranged at the same distance from the axis of rotation and which are connected to the media to be supplied via corresponding connections. The distributor disk is supported by a carrier shaft in the analyzer housing, which also contains a control unit for the rotary and lifting movement of the distributor disk. In a rotary position, the distributor disk has a recess, so that in this position the sample input opening for inputting the sample by means of a pipette or syringe is exposed. With the help of the input device described in DE 38 90 175 C1, the sample can thus be sucked in from a capillary or injected with the help of a plunger syringe, a conical input opening being provided for sealingly receiving the capillary or plunger syringe, which via a rigid, gas-tight Line is connected directly to the measuring cells of the analyzer. However, the input device is not suitable for a third type of input preferred in laboratories, namely input by suction from a plunger syringe. In the device described, when the sample is sucked in from a plunger syringe, a negative pressure would arise inside the plunger syringe and in the piping system of the analyzer, so that when the plunger syringe is removed, the sudden pressure equalization would result in fragmentation of the sample including air bubbles and make the measurement difficult or impossible Measured values ​​would be falsified.

Similar problems when sucking in the sample from a plunger syringe would also be expected with an input device known from EP 0 564 439 A2. For the supply of washing and reference media, a flap is provided which can be pivoted about a fixed axis and via which the washing and reference media are supplied to an elastic input element of the analyzer when the flap is closed. When the flap is open, the input element for sucking in from capillaries or Injection is freely accessible by means of a piston syringe.

AT 413 002 Β

However, sample input devices are also known with which the sample can be sucked in from a plunger syringe. These include a large number of different input devices in which a pivotable input needle is provided so that the sample liquid can be drawn into the analyzer from different sampling vessels in different positions of the needle. In this connection, reference is made to US Pat. No. 4,499,053 A, which shows a mechanically relatively complex lifting mechanism with a link guide, whereby a sample can be sucked in both from a capillary and from a plunger syringe. For this purpose, the input needle has an input element which, with its central opening, can be guided axially on the input needle with the aid of a link control. The input needle can be swiveled up from a rest position, in which the needle is connected to a connection for a washing solution, into several different positions by a handle of the gate control, whereby - due to the gate control - the input element is in different positions along the

The axis of the input needle.

In one of the stroke positions, the needle tip is completely free so that it can be immersed in open sample vessels and the sample is then sucked in. In a further stroke position, the needle tip is located within the central opening of the input element, so that a sample capillary can be pushed into the remaining free area of ​​the central opening and held there. The sample can then be sucked in by the pump of the analyzer.

Finally, a further stroke position is provided in which the input needle assumes an essentially horizontal position and the input element a small part of the

Releases needle tip. The cone of a plunger syringe can now be guided over the needle tip and pressed against the outer surface of the input element, after which the sample is injected into the analyzer. A disadvantage that should be mentioned is that the plunger syringe is not held by the input device, that the outer surface of the input element only provides an inadequate sealing function and there is a risk that parts of the sample will die

Contaminate the input device.

A major disadvantage of the input device according to US Pat. No. 4,499,053 A is that the pivotable needle is connected to the measuring cells via a flexible hose on the device side and moving parts and flexible, gas-permeable hoses in the area between the sample input and the measuring cells are to be avoided.

Similar problems with flexible line systems also occur with known devices in which the input needle is guided into the interior of a plunger syringe with the aid of a drive device.

In this context, US Pat. No. 5,391,499 A describes an input system in which sample input is possible with two different sampling vessels, namely with a plunger syringe (see FIG. 1) or a sample capillary (see FIG. 2). With the help of a rotatable element in the sample input area, the diameter of the sampling vessel can be used to automatically determine whether a plunger syringe or a sample capillary has been inserted into the input opening and thus a different input program can be started for the two input types. With the help of a drive unit, the input needle is either moved forwards in the longitudinal direction in order to penetrate the plunger syringe or withdrawn to make room for a capillary. Because of the longitudinally displaceable input needle of US Pat. No. 5,391,499 A, a flexible (and thus gas-permeable) hose is also necessary for the connection to the measuring cell, which according to the above statements is disadvantageous and should be avoided. Another disadvantage of the input system according to US Pat. No. 5,391,499 A is that it does not allow the sample to be injected from a plunger syringe, since the sample with lateral openings for supplying and removing the

Wash solution would leak.

AT413 002B

It is also known to use different adapters for different sampling vessels, which adapters have to be placed on or inserted into the actual input element of the analyzer. However, this increases the manipulation effort considerably and increases the risk of incorrect operation.

The object of the present invention is to develop a sample input device for the input of medical samples, preferably blood samples, in such a way that sampling from different sampling vessels is possible in the simplest possible mechanical manner, with the sample being transported between the sample input and the measuring cells of the

Analyzer should continue to take place via preferably rigid, gas-tight lines.

According to the invention, this object is achieved in that a stationary input needle is provided, which is arranged on the sample input side and has an elastic input element with a conical input opening, which is axially displaceable on the input needle, as well as a further axially displaceable with respect to the input element and parallel to the input needle displaceable retaining element is provided, which in a first position releases the input element and in a second position positions a conical opening above the input element for receiving a plunger syringe. Advantageously, in the first position of the holding element, in which the conical input opening of the elastic input element is released, the sample can either be sucked in from a capillary or injected with the aid of a plunger syringe. In the second position, which, starting from the first position, is achieved by a translational or rotational displacement of the holding element, the holding element is used to hold the plunger syringe, which is positioned above the input needle and is subsequently lifted by the

Holding element is pushed over the input needle. The sample can then be sucked out of the interior of the plunger syringe, in which case ambient air can flow in through the annular gap between the input needle and the syringe cone in order to avoid negative pressure.

According to a first embodiment variant of the invention, the holding element can be rotatably mounted about an axis of rotation aligned parallel to the input needle at a distance r, so that in a first rotational position the input element is exposed and in a second rotational position above the input element the conical opening for receiving the Piston syringe is positioned.

According to a second variant, the holding element can be designed as a flap and can be rotatably mounted about an axis of rotation lying in a normal plane of the input needle, so that in a first folded position the input element is exposed and in a second folded position above the input element the conical opening for receiving the plunger syringe is positioned.

According to the invention it is provided that the analyzer has a drive unit controlled by a processor unit of the analyzer for the lifting and rotating movement or lifting and folding movement of the holding element.

A further development of the invention provides that the analyzer has a drive unit controlled by a processor unit of the analyzer for the axial displacement of the elastic input element from a first position in the area of ​​the tip of the input needle to a second position in which the needle tip protrudes over the input element , so which is connected to the elastic input element via an actuating element.

A particularly advantageous embodiment of the invention is that the holding element is designed as a distributor disk for the supply of calibration, quality control and / or washing media, with connections for calibration, quality control and / or washing media at a distance r in further rotational positions of the distributor disk / or washing media provided

AT413 002B, which can be brought into contact with the input element.

The invention is explained in more detail below with reference to drawings.

1 to 4 show, in a partially schematic representation, a first variant of the sample input device according to the invention for inputting medical samples into an analyzer in different operating states, each in a sectional view, FIG. 5 shows a plan view of the sample input device according to FIGS. 1 to 4, and FIG. 6 shows a further embodiment variant of the invention in a sectional illustration according to FIG. 3.

The embodiment variant shown in FIGS. 1 to 5 of a sample input device 1 for an analyzer 3 indicated by its front plate 2 has a rigid input needle 4, for example a steel needle, which is connected to the measuring cells 6 in the analyzer 3 via a rigid, gas-tight sample line 5 Connection. The input needle 4 has a device side

Coupling element 7 so that it can be replaced if necessary.

An axially displaceable, elastic input element 8 with a conical input opening 9 is arranged on the input needle 4, the conical opening 9 both for sealingly receiving a sample capillary 10 (see FIG. 1) and the connecting cone of a plunger 20 syringe 11 (see FIG. 2 ) suitable is. The axial displacement of the input element 8 takes place via an actuating element 13 with the aid of a drive unit 12 which is arranged in the analyzer 3 and is controlled by a processor unit 14. The axial displacement of the elastic input element 8 takes place between a first position (see FIGS. 1 to 3) in which the input element 8 is present in the region of the tip 15 of the input needle 4 and a position in the middle region of the input needle 4 (see FIG. 4), in which the tip 15 of the needle protrudes beyond the input element 8.

Furthermore, the input device has an axially displaceable retaining element 16 rotatably mounted about the axis 16 'at a distance r from the input needle 4, which in a first rotational position (FIGS. 1, 2 and 5) releases the input element 8 for certain types of sample input and in a second position rotated by the angle β (Fig. 3 and 4) a conical opening 17 arranged in the holding element 16 for receiving a plunger syringe 11 is positioned above the elastic input element 8 in such a way that the axis 4 ′ of the rigid input needle 4 coincides with the axis 17 ′ of the conical opening 17. A further drive unit 18 controlled by the processor unit 14 is provided in the analyzer 3 for the lifting and rotating movement of the holding element 16.

The sample input device according to the invention is therefore ideally suited for the three preferred types of sample input:

Sucking in the sample from sample tubes with a small diameter, for example from a sample capillary: For this purpose, the input device is in the operating state shown in FIG. 1, that is, the elastic input element 8 is located in the area of ​​the tip 15 of the rigid input needle 4 and the holding element 16 in its first

Rotary position in which the input element 8 is released for the sample input by means of the sample capillary 10. The sample capillary 10 is now inserted into the conical input opening 9 of the elastic input element 8 until it is held in a sealing manner in the guide opening for the input needle 4. Then a pump device (not shown) of the analyzer 3 is activated and the sample is sucked from the sample capillary into the analyzer. The suction process can be started manually via a display of the analyzer or automatically, for example, via optical detection means (not shown further) in the area of ​​the input opening 9, which can differentiate between different sampling vessels at different diameters.

Injecting the sample from a plunger syringe: This type of sample input is shown in FIG. 2

AT 413 002 Β shown schematically. For this purpose, the sample input device 1 is in the same starting position as in FIG. 1, in which case the connecting cone 20 of the plunger syringe 11 is inserted sealingly into the conical input opening 9 of the elastic input element 8 The sample located in the piston syringe 11 is injected into the analyzer 3. The force exerted by the injection process on the axially displaceable input element 8 is supported by the actuation element 13 of the drive unit 12.

Sucking in the sample from a plunger syringe: This type of sample input is shown in FIGS. 3 and 4, the sample input device 1 first being brought into an initial position according to FIG. 3, in which the holding element 16 is arranged in its second rotational position. The conical opening 17 of the holding element is positioned over the input element 8 in such a way that the axis 4 ′ of the rigid input needle 4 coincides with the axis 17 ′ of the conical opening 17. Then the piston syringe 11 with its connecting cone 20 is inserted into the conical opening of the holding element 16 and held there. 4, a lifting movement of both the holding element 16 and the input element 8 is initiated, with which both parts are moved in the direction of the front plate 2 of the analyzer 3. As a result of the lifting movement, the plunger syringe 11 is pulled over the rigid input needle 4 so that it enters the interior of the

Piston syringe penetrates into a bubble-free area of ​​the sample present there. As shown in FIGS. 1 to 4, the rigid input needle 4 is directed slightly obliquely upwards at an angle α and the holding element 16 is inclined at the same angle α, so that the piston syringe 11 also assumes an advantageous position around the sample as far as possible to be able to suck bubble-free from the plunger syringe. Between the input element 8 and the holding element 16, ambient air can flow into the plunger syringe 11 via an annular gap between the input needle 4 and the connecting cone 20 in order to avoid the creation of a negative pressure during sampling. The lifting and rotating movements necessary for this type of sample input can either be initiated manually via a display (preferably touch screen) of the analyzer or automatically by an optical or mechanical detection device for the sampling vessel used - not shown further.

As indicated in Fig. 3 or 5, the holding element 16 can be designed as a distributor disk for the supply of calibration, quality control and / or washing media, with connections 22 in further positions on the underside at a distance from the axis of rotation 16 ' the distributor disk 16 are arranged. Each of these connections 22 can be introduced into the elastic input element 8 by means of a corresponding lifting and rotating movement and the corresponding calibration, quality control and / or washing medium can thus be sucked into the input needle 4.

In the embodiment variant shown in FIG. 6, the holding element 16 is designed as a flap mounted on one side. The axis of rotation 16 lies at a distance r in a normal plane ε of the input needle 4 and supports the flap on a support element 23, which executes the necessary lifting movement in order to pull the plunger syringe 11 over the rigid input needle 4. In a first folded position of the holding element 16 (dashed lines) the input element 8 is exposed for sample input, for example from a capillary; In a second folded position, the conical opening 17 of the flap is folded over the input element 8 to accommodate the plunger syringe 11.

As indicated in Fig. 6 with arrow 24, according to a further embodiment variant - the holding element 16 can also be brought translationally from a first position (input element 8 free) into a second position (conical opening 17 above input element 8) and then a Lifting movement can be carried out with the aid of the support element 23.

It is thus guaranteed that the sample can be entered with all preferred types of sample input

AT413 002B as well as all calibration, quality control and washing media travel the same analysis path.